Texaphyrin coordination compounds and uses thereof

ABSTRACT

Novel coordination polymers, their pharmaceutical formulations, useful for treating atheroma, tumors and other neoplastic tissue, as well as other conditions that are responsive to the induction of targeted oxidative stress, are disclosed.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to novel compounds and their pharmaceuticalformulations, and their uses to treat atheroma, tumors and otherneoplastic tissue, as well as other conditions that are responsive tothe induction of targeted oxidative stress.

2. Background Information

Treatment of solid mammalian tumors with ionizing radiation involves thein situ generation of hydroxyl radicals and other reactive oxygenspecies that, due to the focusability of the ionizing radiation areprimarily located in the tumor, i.e., in tumor cells. These reactivespecies possess extreme oxidizing properties which oxidize biomoleculesin vivo thereby interfering with cellular metabolism, as discussed byBuettner, et al., Radiation Research, Catalytic Metals, Ascorbate andFree Radicals: Combinations to Avoid, 145:532-541 (1996).

Tumor treatment via the use of ionizing radiation can be enhanced byincreasing the radio sensitivity of the tumor cells. One methodsuggested for enhancing radio sensitivity has been the externaladministration of a compound having a high affinity for electrons, whichideally localizes in the tumor. Proposed radiation sensitizers includecompounds such as halogenated pyrimidines, nitroimidazoles andgadolinium (III) complexes of the pentadentate macrocycle Texaphyrin, asdescribed by Sessler, et al., J. Phys. Chem. A, One-Electron Reductionand Oxidation Studies of the Radiations Sensitizer Gadolinium (III)Texaphyrin (PCI-120) and Other Water Soluble Metallotexaphyrins, 103:787-794 (1999).

Texaphyrins are known to be useful as radiation sensitizers, and alsofor the treatment of plaque caused by atherosclerosis, retinal diseases,for the destruction of retroviruses, especially HIV and the like.

Efficacy of texaphyrins is dependent on its ability to penetratecellular membranes and thereby increase its intracellular concentration.Thus intracellular availability of texaphyrin is a key to its biologicalactivity and effectiveness. Texaphyrins are known to penetrate cellmembranes and are known to have an effective intracellular concentrationto have beneficial biological activity. An improvement in the ability ofa drug substance to enter cellular membranes is however always welcome.It has been surprisingly discovered that premixing texaphyrins with anoxalate salt or an oxalate precursor, for example ascorbic acid, givesrise to a compound whose structure differs from that of a Texaphyrin,but is seen to accumulate more rapidly in tumor cells, plaque, etc.

SUMMARY OF THE INVENTION

This invention relates to a method of treating tumors and otherneoplastic tissue, plaque caused by atherosclerosis, viruses, includingHIV, and retinal diseases using the polymeric complex of the presentinvention.

The present invention also relates to polymeric complexes formed bytreating texaphyrins with oxalate salts or oxalate precursors and theirpharmaceutical compositions.

The present invention thus provides a method for treating a disease orcondition in a mammal resulting from the presence of neoplastic tissue,neovascularization, or an atheroma, said method comprising:

-   -   (a) administering to a mammal in need of such treatment a        therapeutically effective amount of a coordination polymer        comprising structural units “A”:        wherein:    -   M is a trivalent metal cation;    -   R¹, R², R³, R⁴, R⁶, R⁷, R⁸, and R⁹ are independently chosen from        the group consisting of hydrogen, halogen, hydroxyl, optionally        substituted alkyl, optionally substituted alkenyl, optionally        substituted alkynyl, optionally substituted aryl, optionally        substituted heteroaryl, nitro, acyl, optionally substituted        alkoxy, alkylalkoxy, saccharide, optionally substituted amino,        carboxyl, optionally substituted carboxyalkyl, optionally        substituted carboxyamide, optionally substituted        carboxyamidealkyl, optionally substituted heterocycle,        optionally substituted cycloalkyl, optionally substituted        arylalkyl, optionally substituted heteroarylalkyl, optionally        substituted heterocycloalkylalkyl; and a group —X—Y, in which X        is a covalent bond or a linker and Y is a catalytic group, a        chemotherapeutic agent, or a site-directing molecule, and    -   R⁵, R¹⁰, R¹¹, and R¹² are independently hydrogen, optionally        substituted alkyl, optionally substituted aryl, optionally        substituted alkoxy, optionally substituted carboxyalkyl, or        optionally substituted carboxyamidealkyl, and    -   structural unit “B”

Another aspect of the present invention provides a coordination polymercomprising structural units “A”:

wherein:

-   -   M is a trivalent metal cation;    -   R¹, R², R³, R⁴, R⁶, R⁷, R⁸, and R⁹ are independently chosen from        the group consisting of hydrogen, halogen, hydroxyl, optionally        substituted alkyl, optionally substituted alkenyl, optionally        substituted alkynyl, optionally substituted aryl, optionally        substituted heteroaryl, nitro, acyl, optionally substituted        alkoxy, alkylalkoxy, saccharide, optionally substituted amino,        carboxyl, optionally substituted carboxyalkyl, optionally        substituted carboxyamide, optionally substituted        carboxyamidealkyl, optionally substituted heterocycle,        optionally substituted cycloalkyl, optionally substituted        arylalkyl, optionally substituted heteroarylalkyl, optionally        substituted heterocycloalkylalkyl; and a group —X—Y, in which X        is a covalent bond or a linker and Y is a catalytic group, a        chemotherapeutic agent, or a site-directing molecule, and    -   R⁵, R¹⁰, R¹¹, and R¹² are independently hydrogen, optionally        substituted alkyl, optionally substituted aryl, optionally        substituted alkoxy, optionally substituted carboxyalkyl, or        optionally substituted carboxyamidealkyl, and    -   structural unit “B”

Provided in yet another aspect is a coordination polymer whereinstructural unit “A” is represented by

wherein

-   -   M independently at each occurrence represents Gd(III) or        Lu(III); and structural unit “B” is represented by

Yet another aspect provides a process of making a coordination polymercomprising structural units “A”:

wherein:

-   -   M is a trivalent metal cation;    -   AL is an apical ligand;    -   n is an integer of 1-5;    -   R¹, R², R³, R⁴, R⁶, R⁷, R⁸, and R⁹ are independently chosen from        the group consisting of hydrogen, halogen, hydroxyl, optionally        substituted alkyl, optionally substituted alkenyl, optionally        substituted alkynyl, optionally substituted aryl, optionally        substituted heteroaryl, nitro, acyl, optionally substituted        alkoxy, alkylalkoxy, saccharide, optionally substituted amino,        carboxyl, optionally substituted carboxyalkyl, optionally        substituted carboxyamide, optionally substituted        carboxyamidealkyl, optionally substituted heterocycle,        optionally substituted cycloalkyl, optionally substituted        arylalkyl, optionally substituted heteroarylalkyl, optionally        substituted heterocycloalkylalkyl; and a group —X—Y, in which X        is a covalent bond or a linker and Y is a catalytic group, a        chemotherapeutic agent, or a site-directing molecule, and    -   R⁵, R¹⁰, R¹¹; and R¹² are independently hydrogen, optionally        substituted alkyl, optionally substituted aryl, optionally        substituted alkoxy, optionally substituted carboxyalkyl, or        optionally substituted carboxyamidealkyl; and    -   structural unit “B”        said process comprising contacting a compound of Formula A        wherein    -   M is a trivalent metal cation;    -   AL is an apical ligand;    -   n is an integer of 1-5;    -   R¹, R², R³, R⁴, R⁶, R⁷, R⁸, and R⁹ are independently chosen from        the group consisting of hydrogen, halogen, hydroxyl, optionally        substituted alkyl, optionally substituted alkenyl, optionally        substituted alkynyl, optionally substituted aryl, optionally        substituted heteroaryl, nitro, acyl, optionally substituted        alkoxy, alkylalkoxy, saccharide, optionally substituted amino,        carboxyl, optionally substituted carboxyalkyl, optionally        substituted carboxyamide, optionally substituted        carboxyamidealkyl, optionally substituted heterocycle,        optionally substituted cycloalkyl, optionally substituted        arylalkyl, optionally substituted heteroarylalkyl, optionally        substituted heterocycloalkylalkyl; and a group —X—Y, in which X        is a covalent bond or a linker and Y is a catalytic group, a        chemotherapeutic agent, or a site-directing molecule, and    -   R⁵, R¹⁰, R¹¹, and R¹² are independently hydrogen, optionally        substituted alkyl, optionally substituted aryl, optionally        substituted alkoxy, optionally substituted carboxyalkyl, or        optionally substituted carboxyamidealkyl;    -   with an oxalate salt or an oxalate precursor, to form a        coordination polymer comprising structural units “A” and “B”.

Also provided is a coordination polymer prepared by contacting acompound of Formula A

wherein:

-   -   M is a trivalent metal cation;    -   AL is an apical ligand;    -   n is an integer of 1-5;    -   R¹, R², R³, R⁴, R⁶, R⁷, R⁸, and R⁹ are independently chosen from        the group consisting of hydrogen, halogen, hydroxyl, optionally        substituted alkyl, optionally substituted alkenyl, optionally        substituted alkynyl, optionally substituted aryl, optionally        substituted heteroaryl, nitro, acyl, optionally substituted        alkoxy, alkylalkoxy, saccharide, optionally substituted amino,        carboxyl, optionally substituted carboxyalkyl, optionally        substituted carboxyamide, optionally substituted        carboxyamidealkyl, optionally substituted heterocycle,        optionally substituted cycloalkyl, optionally substituted        arylalkyl, optionally substituted heteroarylalkyl, option ally        substituted heterocycloalkylalkyl; and a group —X—Y, in which X        is a covalent bond or a linker and Y is a catalytic group, a        chemotherapeutic agent, or a site-directing molecule, and    -   R⁵, R¹⁰, R¹¹, and R¹² are independently hydrogen, optionally        substituted alkyl, optionally substituted aryl, optionally        substituted alkoxy, optionally substituted carboxyalkyl, or        optionally substituted carboxyamidealkyl;    -   with an oxalate salt or an oxalate precursor, optionally in the        presence of oxygen.

DETAILED DESCRIPTION OF THE INVENTION

The present invention thus provides a method for treating a disease orcondition in a mammal resulting from the presence of neoplastic tissue,neovascularization, or an atheroma, said method comprising:

-   -   (a) administering to a mammal in need of such treatment a        therapeutically effective amount of a coordination polymer        comprising structural units “A”:        wherein:    -   M is a trivalent metal cation;    -   R¹, R², R³, R⁴, R⁶, R⁷, R⁸, and R⁹ are independently chosen from        the group consisting of hydrogen, halogen, hydroxyl, optionally        substituted alkyl, optionally substituted alkenyl, optionally        substituted alkynyl, optionally substituted aryl, optionally        substituted heteroaryl, nitro, acyl, optionally substituted        alkoxy, alkylalkoxy, saccharide, optionally substituted amino,        carboxyl, optionally substituted carboxyalkyl, optionally        substituted carboxyamide, optionally substituted        carboxyamidealkyl, optionally substituted heterocycle,        optionally substituted cycloalkyl, optionally substituted        arylalkyl, optionally substituted heteroarylalkyl, optionally        substituted heterocycloalkylalkyl; and a group —X—Y, in which X        is a covalent bond or a linker and Y is a catalytic group, a        chemotherapeutic agent, or a site-directing molecule, and    -   R⁵, R¹⁰, R¹¹, and R¹² are independently hydrogen, optionally        substituted alkyl, optionally substituted aryl, optionally        substituted alkoxy, optionally substituted carboxyalkyl, or        optionally substituted carboxyamidealkyl, and    -   structural unit “B”

A preferred embodiment provides a method wherein within structural unit“A”

-   -   M independently at each occurrence represents Gd(III), Lu(III),        Eu(III), Tb(III), Dy(III), Ho(III), Er(III), Tm(III), Yb(III),        or Y(III);    -   R¹ represents (CH₂)₂₋₄—OH;    -   R² and R³ independently represent C₁-C₃-alkyl;    -   R⁴ represents ethyl, methyl or propyl;    -   R⁵, R⁶, R⁹, R¹⁰, R¹¹ and R¹² independently represent H or        methyl; and    -   R⁷ and R⁸ represent O—[(CH₂)₂O]₃—C₁₋₂-alkyl or O—(CH₂)₂₋₄OH.

A further preferred embodiment provides a method of Claim 2 whereinstructural unit “A” is represented by

wherein,

-   -   M independently at each occurrence represents Gd(III), Lu(III),        Eu(III), Tb(III), Dy(III), Ho(III), Er(III), Tm(III), Yb(III),        or Y(III).

Another preferred embodiment provides a method wherein said methodfurther comprises treating the area in proximity to the neoplastictissue with a therapeutic energy means or with a chemotherapeutic agent,or treating the area in proximity to the neovascularization or atheromawith a therapeutic energy means; and wherein the optional therapeuticenergy means is chosen from photoirradiation, ionizing radiation,neutron irradiation, and ultrasound.

Another aspect of the present invention provides a coordination polymercomprising structural units “A”:

wherein:

-   -   M is a trivalent metal cation;    -   R¹, R², R³, R⁴, R⁶, R⁷, R⁸, and R⁹ are independently chosen from        the group consisting of hydrogen, halogen, hydroxyl, optionally        substituted alkyl, optionally substituted alkenyl, optionally        substituted alkynyl, optionally substituted aryl, optionally        substituted heteroaryl, nitro, acyl, optionally substituted        alkoxy, alkylalkoxy, saccharide, optionally substituted amino,        carboxyl, optionally substituted carboxyalkyl, optionally        substituted carboxyamide, optionally substituted        carboxyamidealkyl, optionally substituted heterocycle,        optionally substituted cycloalkyl, optionally substituted        arylalkyl, optionally substituted heteroarylalkyl, optionally        substituted heterocycloalkylalkyl; and a group —X—Y, in which X        is a covalent bond or a linker and Y is a catalytic group, a        chemotherapeutic agent, or a site-directing molecule, and    -   R⁵, R¹⁰, R¹¹, and R¹² are independently hydrogen, optionally        substituted alkyl, optionally substituted aryl, optionally        substituted alkoxy, optionally substituted carboxyalkyl, or        optionally substituted carboxyamidealkyl, and    -   structural unit “B”        A preferred coordination polymer is one wherein within        structural unit “A”, M independently at each occurrence        represents Gd(III), Lu(III), Eu(III), Tb(III), Dy(III), Ho(III),        Er(III), Tm(III), Yb(III), or Y(III);    -   R¹ represents (CH₂)₂₋₄—OH;    -   R² and R³ independently represent C₁-C₃-alkyl;    -   R⁴ represents ethyl, methyl or propyl;    -   R⁵, R⁶, R⁹, R¹⁰, R¹¹ and R¹² independently represent H or        methyl; and    -   R⁷ and R⁸ represent O—[(CH₂)₂O ]₃—C₁₋₂-alkyl or O—(CH₂)₂₋₄OH.

A further preferred coordination polymer comprises structural unit “A”represented by

wherein

-   -   M independently at each occurrence represents Gd(III), Lu(III),        Eu(III), Tb(III), Dy(III), Ho(III), Er(III), Tm(III), Yb(III),        or Y(III).        A particularly preferred coordination polymer comprises a        structural unit “A” is represented by        wherein    -   M independently at each occurrence represents Gd(III) or        Lu(III); and    -   structural unit “B” is represented by        Another particularly preferred coordination polymer comprises a        structural unit “A” represented by        wherein    -   M represents Gd(III); and    -   structural unit “B” is represented by        Yet another particularly preferred coordination polymer        comprises structural unit “A” represented by        wherein    -   M represents Gd(III); and    -   structural unit “B” is represented by

Another aspect of the present invention provides a process of making acoordination polymer comprising structural units “A”:

wherein:

-   -   M is a trivalent metal cation;    -   AL is an apical ligand;    -   n is an integer of 1-5;    -   R¹, R², R³, R⁴, R⁶, R⁷, R⁸, and R⁹ are independently chosen from        the group consisting of hydrogen, halogen, hydroxyl, optionally        substituted alkyl, optionally substituted alkenyl, optionally        substituted alkynyl, optionally substituted aryl, optionally        substituted heteroaryl, nitro, acyl, optionally substituted        alkoxy, alkylalkoxy, saccharide, optionally substituted amino,        carboxyl, optionally substituted carboxyalkyl, optionally        substituted carboxyamide, optionally substituted        carboxyamidealkyl, optionally substituted heterocycle,        optionally substituted cycloalkyl, optionally substituted        arylalkyl, optionally substituted heteroarylalkyl, optionally        substituted heterocycloalkylalkyl; and a group —X—Y, in which X        is a covalent bond or a linker and Y is a catalytic group, a        chemotherapeutic agent, or a site-directing molecule, and    -   R⁵, R¹⁰, R¹¹, and R¹² are independently hydrogen, optionally        substituted alkyl, optionally substituted aryl, optionally        substituted alkoxy, optionally substituted carboxyalkyl, or        optionally substituted carboxyamidealkyl; and    -   structural unit “B”        said process comprising contacting a compound of Formula A        wherein    -   M is a trivalent metal cation;    -   AL is an apical ligand;    -   n is an integer of 1-5;    -   R¹, R², R³, R⁴, R⁶, R⁷, R⁸, and R⁹ are independently chosen from        the group consisting of hydrogen, halogen, hydroxyl, optionally        substituted alkyl, optionally substituted alkenyl, optionally        substituted alkynyl, optionally substituted aryl, optionally        substituted heteroaryl, nitro, acyl, optionally substituted        alkoxy, alkylalkoxy, saccharide, optionally substituted amino,        carboxyl, optionally substituted carboxyalkyl, optionally        substituted carboxyamide, optionally substituted        carboxyamidealkyl, optionally substituted heterocycle,        optionally substituted cycloalkyl, optionally substituted        arylalkyl, optionally substituted heteroarylalkyl, optionally        substituted heterocycloalkylalkyl; and a group —X—Y, in which X        is a covalent bond or a linker and Y is a catalytic group, a        chemotherapeutic agent, or a site-directing molecule, and    -   R⁵, R¹⁰, R¹⁰, and R¹² are independently hydrogen, optionally        substituted alkyl, optionally substituted aryl, optionally        substituted alkoxy, optionally substituted carboxyalkyl, or        optionally substituted carboxyamidealkyl;    -   with an oxalate salt or an oxalate precursor, to form a        coordination polymer comprising structural units “A” and “B”.

A preferred process is one wherein within structural unit “A” Mindependently at each occurrence represents Gd(III), Lu(III), Eu(III),Tb(III), Dy(III), Ho(III), Er(III), Tm(III), Yb(III), or Y(III);

-   -   R¹represents (CH₂)₂₋₄—OH;    -   R² and R³ independently represent C₁-C₃-alkyl;    -   R⁴ represents ethyl, methyl or propyl;    -   R⁵, R⁶, R⁹, R¹⁰, R¹¹ and R¹² independently represent H or        methyl; and    -   R⁷ and R⁸ represent O—[(CH₂)₂O]₃—C₁-₂-alkyl or O—(CH₂)₂₋₄OH.

A further preferred process is one wherein structural unit “A” isrepresented by

and compound of Formula A are represented by

wherein

-   -   M independently at each occurrence represents Gd(III), Lu(III),        Eu(III), Tb(III), Dy(III), Ho(III), Er(III), Tm(III), Yb(III),        or Y(III); the process is carried out at ambient temperature and        neutral pH; the oxalate or oxalate precursor is selected from        ascorbate, dehydroascorbate, glyoxal and glyoxylate; and the        process is carried out in the presence of oxygen.

Yet another aspect of the present invention provides a coordinationpolymer prepared by contacting a compound of Formula A

wherein:

-   -   M is a trivalent metal cation;    -   AL is an apical ligand;    -   n is an integer of 1-5;    -   R¹, R², R³, R⁴, R⁶, R⁷, R⁸, and R⁹ are independently chosen from        the group consisting of hydrogen, halogen, hydroxyl, optionally        substituted alkyl, optionally substituted alkenyl, optionally        substituted alkynyl, optionally substituted aryl, optionally        substituted heteroaryl, nitro, acyl, optionally substituted        alkoxy, alkylalkoxy, saccharide, optionally substituted amino,        carboxyl, optionally substituted carboxyalkyl, optionally        substituted carboxyamide, optionally substituted        carboxyamidealkyl, optionally substituted heterocycle,        optionally substituted cycloalkyl, optionally substituted        arylalkyl, optionally substituted heteroarylalkyl, optionally        substituted heterocycloalkylalkyl; and a group —X—Y, in which X        is a covalent bond or a linker and Y is a catalytic group, a        chemotherapeutic agent, or a site-directing molecule, and    -   R⁵, R¹⁰, R¹¹, and R¹² are independently hydrogen, optionally        substituted alkyl, optionally substituted aryl, optionally        substituted alkoxy, optionally substituted carboxyalkyl, or        optionally substituted carboxyamidealkyl;    -   with an oxalate salt or an oxalate precursor, optionally in the        presence of oxygen.

A preferred coordination polymer is one wherein within structural unit“A”

-   -   M independently at each occurrence represents Gd(III), Lu(III),        Eu(III), Tb(III), Dy(III), Ho(III), Er(III), Tm(III), Yb(III),        or Y(III);    -   R¹represents (CH₂)₂₋₄—OH;    -   R² and R³ independently represent C₁-C₃-alkyl;    -   R⁴ represents ethyl, methyl or propyl;    -   R⁵, R⁶, R⁹, R¹⁰, R¹¹ and R¹² independently represent H or        methyl; and    -   R⁷ and R⁸ represent O—[(CH₂)₂O[₃—C₁-₂-alkyl or O—(CH₂)₂₋₄OH; and        wherein the oxalate precursor is selected from ascorbate,        dehydroascorbate, glyoxal, glyoxalate, oxamate, dimethyloxalate,        and oxamide.

Yet another preferred method is one wherein the compound of Formula A isrepresented by

wherein

-   -   M independently at each occurrence represents Gd(III), Lu(III),        Eu(III), Tb(III), Dy(III), Ho(III), Er(III), Tm(III), Yb(III),        or Y(III); and    -   n represents an integer from 1 to 3.

It has now been discovered that mixing the texaphyrins with a chemicalentity selected from an oxalate, ascorbate, dehydroascorbate,glyoxylate, dimethyl oxalate, and the like, forms a complex comprisingTexaphyrin and oxalate. These complexes have a characteristic UVabsorptions at 510 nm and 780 nm, which differ from that of the startingcompound(s).

This coordination complex, upon administration by injection, improveslocalization of the texaphyrin at the desired site (tumor, plaque, etc.)as compared to the previously known method of injecting texaphyrinalone, and thereby provides a more effective method of treatment.

As used herein, the following terms have the meanings as defined below.

The term “texaphyrin” refers to metal complexes of aromatic pentadentatemacrocyclic “expanded porphyrins” which are considered as being anaromatic benzannulene containing both 18 π and 22 π-electrondelocalization pathways. Such texaphyrins and their synthesis have beendescribed, for example, by Sessler, et al., in U.S. Pat. No. 5,457,183;Sessler, et al., Accounts of Chem. Res., Texaphyrins: Synthesis andApplications, 27:43-50 (1994) and Hemmi, et al., U.S. Pat. No. 5,599,928and are incorporated herein by reference.

The term “alkyl” refers to a monoradical branched or unbranchedsaturated hydrocarbon chain preferably having from 1 to 40 carbon atoms,more preferably 1 to 10 carbon atoms, and even more preferably 1 to 6carbon atoms. This term is exemplified by groups such as methyl, ethyl,n-propyl, iso-propyl, n-butyl, iso-butyl, n-hexyl, n-decyl, tetradecyland the like.

The term “substituted alkyl” refers to an alkyl group as defined above,having from 1 to 5 substituents, and preferably 1 to 3 substituents,selected from the group consisting of alkoxy, substituted alkoxy,cycloalkyl, substituted cycloalkyl, cycloalkenyl, substitutedcycloalkenyl, acyl, acyl amino, acyloxy, amino, substituted amino,aminoacyl, aminoacyloxy, oxyaminoacyl, azido, cyano, halogen, hydroxyl,keto, thioketo, carboxyl, carboxylalkyl, thioaryloxy, thioheteroaryloxy,thioheterocyclooxy, thiol, thioalkoxy, substituted thioalkoxy, aryl,aryloxy, heteroaryl, heteroaryloxy, heterocyclic, heterocyclooxy,hydroxylamine, alkoxyamino, nitro, —SO-alkyl, —SO-substituted alkyl,—SO-aryl, —SO-heteroaryl, —SO₂-alkyl, —SO₂-substituted alkyl, —SO₂-aryland —SO₂-heteroaryl.

The term “alkylene” refers to a diradical of a branched or unbranchedsaturated hydrocarbon chain, preferably having from 2 to 6 carbon atoms,more preferably 2 to 4 carbon atoms. This term is exemplified by groupssuch as ethylene (—CH₂CH₂—), the propylene isomers (e.g., —CH₂CH₂CH₂—and —CH(CH₃)CH₂—) and the like.

The term “substituted alkylene” refers to an alkylene group, as definedabove, having from 1 to 5 substituents, and preferably 1to 3substituents, selected from the group consisting of alkoxy, substitutedalkoxy, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substitutedcycloalkenyl, acyl, acylamino, acyloxy, amino, substituted amino,aminoacyl, aminoacyloxy, oxyaminoacyl, azido, cyano, halogen, hydroxyl,keto, thioketo, carboxyl, carboxylalkyl, thioaryloxy, thioheteroaryloxy,thioheterocyclooxy, thiol, thioalkoxy, substituted thioalkoxy, aryl,aryloxy, heteroaryl, heteroaryloxy, heterocyclic, heterocyclooxy,hydroxylamine, alkoxyamino, nitro, —SO-alkyl, —SO-substituted alkyl,—SO-aryl, —SO-heteroaryl, —SO₂-alkyl, —SO₂-substituted alkyl, —SO₂-aryland —SO₂-heteroaryl. Additionally, such substituted alkylene groupsinclude those where 2 substituents on the alkylene group are fused toform one or more cycloalkyl, substituted cycloalkyl, cycloalkenyl,substituted cycloalkenyl, aryl, heterocyclic or heteroaryl groups fusedto the alkylene group. Preferably such fused groups contain from 1 to 3fused ring structures.

The term “alkoxy” refers to the groups alkyl-O—, alkenyl-O—,cycloalkyl-O— and cycloalkenyl-O—, where alkyl, alkenyl, cycloalkyl, andcycloalkenyl are as defined herein. Preferred alkoxy groups are alkyl-O—and include, by way of example, methoxy, ethoxy, n-propoxy, iso-propoxy,n-butoxy, tert-butoxy, sec-butoxy, n-pentoxy, n-hexoxy,1,2-dimethylbutoxy, and the like.

The term “substituted alkoxy” refers to the groups substituted alkyl-O—,substituted alkenyl-O—, substituted cycloalkyl-O— and substitutedcycloalkenyl-O—, where substituted alkyl, substituted alkenyl,substituted cycloalkyl, and substituted cycloalkenyl are as definedherein. A preferred class of substituted alkoxy are polyoxyalkylenegroups represented by the formula —O(R′O)_(q)R″ where R′ is an alkylenegroup or a substituted alkylene group, R″ is selected from the groupconsisting of hydrogen, alkyl or substituted alkyl and q is an integerfrom 1 to 10. Preferably, in such groups, q is from 1 to 5 and mostpreferably 3.

The term “alkenyl” refers to a monoradical of a branched or unbranchedunsaturated hydrocarbon group preferably having from 2 to 40 carbonatoms, more preferably 2 to 10 carbon atoms and even more preferably 2to 6 carbon atoms and having at least 1 and preferably from 1-6 sites ofvinyl unsaturation. Preferred alkenyl groups include ethenyl (—CH═CH₂),n-propenyl (—CH₂CH═CH₂), iso-propenyl (—C(CH₃)═CH₂), and the like.

The term “substituted alkenyl” refers to an alkenyl group as definedabove having from 1 to 5 substituents, and preferably 1 to 3substituents, selected from the group consisting of alkoxy, substitutedalkoxy, cycloalkyl, substituted cycloalkyl, cycloalkenyl, substitutedcycloalkenyl, acyl, acylamino, acyloxy, amino, substituted amino,aminoacyl, aminoacyloxy, oxyaminoacyl, azido, cyano, halogen, hydroxyl,keto, thioketo, carboxyl, carboxylalkyl, thioaryloxy, thioheteroaryloxy,thioheterocyclooxy, thiol, thioalkoxy, substituted thioalkoxy, aryl,aryloxy, heteroaryl, heteroaryloxy, heterocyclic, heterocyclooxy,hydroxylamine, alkoxyamino, nitro, —SO-alkyl, —SO-substituted alkyl,—SO-aryl, —SO-heteroaryl, —SO₂-alkyl, —SO₂-substituted alkyl, —SO₂-aryland —SO₂-heteroaryl.

The term “acyl” refers to the groups HC(O)—, alkyl-C(O)—, substitutedalkyl-C(O)—, cycloalkyl-C(O)—, substituted cycloalkyl-C(O)—,cycloalkenyl-C(O)—, substituted cycloalkenyl-C(O)—, aryl-C(O)—,heteroaryl-C(O)— and heterocyclic-C(O)— where alkyl, substituted alkyl,cycloalkyl, substituted cycloalkyl, cycloalkenyl, substitutedcycloalkenyl, aryl, heteroaryl and heterocyclic are as defined herein.

The term “acylamino” refers to the group —C(O)NRR where each R isindependently hydrogen, alkyl, substituted alkyl, aryl, heteroaryl,heterocyclic or where both R groups are joined to form a heterocyclicgroup (e.g., morpholino) wherein alkyl, substituted alkyl, aryl,heteroaryl and heterocyclic are as defined herein.

The term “aminoacyl” refers to the group —NRC(O)R where each R isindependently hydrogen, alkyl, substituted alkyl, aryl, heteroaryl, orheterocyclic wherein alkyl, substituted alkyl, aryl, heteroaryl andheterocyclic are as defined herein.

The term “aminoacyloxy” refers to the group —NRC(O)OR where each R isindependently hydrogen, alkyl, substituted alkyl, aryl, heteroaryl, orheterocyclic wherein alkyl, substituted alkyl, aryl, heteroaryl andheterocyclic are as defined herein.

The term “acyloxy” refers to the groups alkyl-C(O)O—, substitutedalkyl-C(O)O—, cycloalkyl-C(O)O—, substituted cycloalkyl-C(O)O—,aryl-C(O)O—, heteroaryl-C(O)O—, and heterocyclic-C(O)O— wherein alkyl,substituted alkyl, cycloalkyl, substituted cycloalkyl, aryl, heteroaryl,and heterocyclic are as defined herein.

The term “aryl” refers to an unsaturated aromatic carbocyclic group offrom 6 to 20 carbon atoms having a single ring (e.g., phenyl) ormultiple condensed (fused)rings (e.g., naphthyl or anthryl). Preferredaryls include phenyl, naphthyl and the like.

Unless otherwise constrained by the definition for the aryl substituent,such aryl groups can optionally be substituted with from 1 to 5substituents, preferably 1 to 3 substituents, selected from the groupconsisting of acyloxy, hydroxy, thiol, acyl, alkyl, alkoxy, alkenyl,cycloalkyl, cycloalkenyl, substituted alkyl, substituted alkoxy,substituted alkenyl, substituted cycloalkyl, substituted cycloalkenyl,amino, substituted amino, aminoacyl, acylamino, alkaryl, aryl, aryloxy,azido, carboxyl, carboxylalkyl, cyano, halo, nitro, heteroaryl,heteroaryloxy, heterocyclic, heterocyclooxy, aminoacyloxy, oxyacylamino,thioalkoxy, substituted thioalkoxy, thioaryloxy, thioheteroaryloxy,—SO-alkyl, —SO-substituted alkyl, —SO-aryl, —SO-heteroaryl, —SO₂-alkyl,—SO₂-substituted alkyl, —SO₂-aryl, —SO₂-heteroaryl and trihalomethyl.Preferred aryl substituents include alkyl, alkoxy, halo, cyano, nitro,trihalomethyl, and thioalkoxy.

The term “aryloxy” refers to the group aryl-O— wherein the aryl group isas defined above including optionally substituted aryl groups as alsodefined above.

The term “amino” refers to the group —NH₂.

The term “substituted amino refers to the group —NRR where each R isindependently selected from the group consisting of hydrogen, alkyl,substituted alkyl, cycloalkyl, substituted cycloalkyl, alkenyl,substituted alkenyl, cycloalkenyl, substituted cycloalkenyl, aryl,heteroaryl and heterocyclic provided that both R's are not hydrogen.

The term “carboxyalkyl” refers to the groups “—C(O)O-alkyl”,“—C(O)O-substituted alkyl”, “—C(O)O-cycloalkyl”, “—C(O)O-substitutedcycloalkyl”, “—C(O)O-alkenyl”, and “—C(O)O-substituted alkenyl”, wherealkyl, substituted alkyl, cycloalkyl, substituted cycloalkyl, alkenyl,and substituted alkenyl, are as defined herein.

The term “cycloalkyl” refers to cyclic alkyl groups of from 3 to 20carbon atoms having a single cyclic ring or multiple condensed rings.Such cycloalkyl groups include, by way of example, single ringstructures such as cyclopropyl, cyclobutyl, cyclopentyl, cyclooctyl, andthe like, or multiple ring structures such as adamantanyl, and the like.

The term “substituted cycloalkyl” refers to cycloalkyl groups havingfrom 1 to 5 substituents, and preferably 1 to 3 substituents, selectedfrom the group consisting of alkoxy, substituted alkoxy, cycloalkyl,substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, acyl,acylamino, acyloxy, amino, substituted amino, aminoacyl, aminoacyloxy,oxyaminoacyl, azido, cyano, halogen, hydroxyl, keto thioketo, carboxyl,carboxylalkyl, thioaryloxy, thioheteroaryloxy, thioheterocyclooxy,thiol, thioalkoxy, substituted thioalkoxy, aryl, aryloxy, heteroaryl,heteroaryloxy, heterocyclic, heterocyclooxy, hydroxylamine, alkoxyamino,nitro, —O-alkyl, —SO-substituted alkyl, —SO-aryl, —SO-heteroaryl,—SO₂-alkyl, —SO₂-substituted alkyl, —SO₂-aryl and —SO₂-heteroaryl.

The term “cycloalkenyl” refers to cyclic alkenyl groups of from 4 to 20carbon atoms having a single cyclic ring and at least one point ofinternal unsaturation. Examples of suitable cycloalkenyl groups include,for instance, cyclobut-2-enyl, cyclopent-3-enyl, cyclooct-3-enyl and thelike.

The term “substituted cycloalkenyl” refers to cycloalkenyl groups havingfrom 1 to 5 substituents, and preferably 1 to 3 substituents, selectedfrom the group consisting of alkoxy, substituted alkoxy, cycloalkyl,substituted cycloalkyl, cycloalkenyl, substituted cycloalkenyl, acyl,acylamino, acyloxy, amino, substituted amino, aminoacyl, aminoacyloxy,oxyaminoacyl, azido, cyano, halogen, hydroxyl, keto, thioketo, carboxyl,carboxylalkyl, thioaryloxy, thioheteroaryloxy, thioheterocyclooxy,thiol, thioalkoxy, substituted thioalkoxy, aryl, aryloxy, heteroaryl,heteroaryloxy, heterocyclic, heterocyclooxy, hydroxylamine, alkoxyamino,nitro, —SO-alkyl, —SO-substituted alkyl, —SO-aryl, —SO-heteroaryl,—SO₂-alkyl, —SO₂substituted alkyl, —SO₂-aryl and —SO₂-heteroaryl.

The term “halo” or “halogen” refers to fluoro, chloro, bromo and iodo.

The term “heteroaryl” refers to an aromatic group of from 1 to 15 carbonatoms and 1 to 4 heteroatoms selected from oxygen, nitrogen and sulfurwithin at least one ring (if there is more than one ring).

Unless otherwise constrained by the definition for the heteroarylsubstituent, such heteroaryl groups can be optionally substituted with 1to 5 substituents, preferably 1 to 3 substituents, selected from thegroup consisting of acyloxy, hydroxy, thiol, acyl, alkyl, alkoxy,alkenyl, cycloalkyl, cycloalkenyl, substituted alkyl, substitutedalkoxy, substituted alkenyl, substituted cycloalkyl, substitutedcycloalkenyl amino, substituted amino, aminoacyl, acylamino, alkaryl,aryl, aryloxy, azido, carboxyl, carboxylalkyl, cyano, halo, nitro,heteroaryl, heteroaryloxy, heterocyclic, heterocyclooxy, aminoacyloxy,oxyacylamino, thioalkoxy, substituted thioalkoxy, thioaryloxy,thioheteroaryloxy, —SO-alkyl, —SO-substituted alkyl, —SO-aryl,—SO-heteroaryl, —SO₂-alkyl, —SO₂-substituted alkyl, —SO₂-aryl,—SO₂-heteroaryl and trihalomethyl. Preferred aryl substituents includealkyl, alkoxy, halo, cyano, nitro, trihalomethyl, and thioalkoxy. Suchheteroaryl groups can have a single ring (e.g., pyridyl or furyl) ormultiple condensed rings (e.g., indolizinyl or benzothienyl). Preferredheteroaryls include pyridyl, pyrrolyl and furyl.

The term “heteroaryloxy” refers to the group heteroaryl-O—.

The term “heterocycle” or “heterocyclic” refers to a monoradicalsaturated unsaturated group having a single ring or multiple condensedrings, from 1 to 40 carbon atoms and from 1 to 10 hetero atoms,preferably 1 to 4 heteroatoms, selected from nitrogen, sulfur,phosphorus, and oxygen within the ring.

Unless otherwise constrained by the definition for the heterocyclicsubstituent, such heterocyclic groups can be optionally substituted with1 to 5, and preferably 1 to 3 substituents, selected from the groupconsisting of alkoxy, substituted alkoxy, cycloalkyl, substitutedcycloalkyl, cycloalkenyl, substituted cycloalkenyl, acyl, acylamino,acyloxy, amino, substituted amino, aminoacyl, aminoacyloxy,oxyaminoacyl, azido, cyano, halogen, hydroxyl, keto, thioketo, carboxyl,carboxylalkyl, thioaryloxy, thioheteroaryloxy, thioheterocyclooxy,thiol, thioalkoxy, substituted thioalkoxy, aryl, aryloxy, heteroaryl,heteroaryloxy, heterocyclic, heterocyclooxy, hydroxylamine, alkoxyamino,nitro, —SO-alkyl, —SO-substituted alkyl, —SO-aryl, —SO-heteroaryl,—SO₂-alkyl, —SO₂-substituted alkyl, —SO₂-aryl and —SO₂-heteroaryl. Suchheterocyclic groups can have a single ring or multiple condensed rings.Preferred heterocyclics include morpholino, piperidinyl, and the like.

Illustrative examples of nitrogen heterocycles and heteroaryls arepyrrole, imidazole, pyrazole, pyridine, pyrazine, pyrimidine,pyridazine, indolizine, isoindole, indole, indazole, purine,quinolizine, isoquinoline, quinoline phthalazine, naphthylpyridine,quinoxaline, quinazoline, cinnoline, pteridine, carbazole, carboline,phenanthridine, acridine, phenanthroline, isothiazole, phenazine,isoxazole, phenoxazine, phenothiazine, imidazolidine, imidazoline,piperidine, piperazine, indoline, morpholino, piperidinyl,tetrahydrofuranyl, and the like as well as N-alkoxy-nitrogen containingheterocycles.

The term “heterocyclooxy” refers to the group heterocyclic-O—.

The term “thioheterocyclooxy” refers to the group heterocyclic-S—.

The term “oxyacylamino” refers to the group —OC(O)NRR where each R isindependently hydrogen, alkyl, substituted alkyl, aryl, heteroaryl, orheterocyclic wherein alkyl, substituted alkyl, aryl, heteroaryl andheterocyclic are as defined herein.

The term “thiol” refers to the group —SH.

The term “thioalkoxy” refers to the group —S-alkyl.

The term “substituted thioalkoxy” refers to the group —S-substitutedalkyl.

The term “thioaryloxy” refers to the group aryl-S— wherein the arylgroup is as defined above including optionally substituted aryl groupsalso defined above.

The term “thioheteroaryloxy” refers to the group heteroaryl-S— whereinthe heteroaryl group is as defined above including optionallysubstituted aryl groups as also defined above.

The term “saccharide” refers to oxidized, reduced or substitutedsaccharides hexoses such as D-glucose, D-mannose, D-xylose, D-galactose,D-glucuronic acid, N-acetyl-D-glucosamine, N-acetyl-D-galactosamine,sialyic acid, iduronic acid, L-fucose, and the like; pentoses such asD-ribose or D-arabinose; ketoses such as D-ribulose or D-fructose;disaccharides such as sucrose, lactose, or maltose; derivatives such asacetals, amines, acylated, sulfated and phosphorylated sugars;oligosaccharides having from 2 to 10 saccharide units. For the purposesof this definition, these saccharides are referenced using conventionalthree letter nomenclature and the saccharides can be either in theiropen or preferably in their pyranose form.

As to any of the above groups that contain one or more substituents, itis understod of course, that such groups do not contain any substitutionor substitution patterns which are sterically impractical and/orsynthetically non-feasible. In addition, the compounds of this inventioninclude all stereochemical isomers and mixtures thereof arising from thesubstitution of these compounds.

The term “treatment” or “treating” means any treatment of a disease in amammal, including:

-   -   (i) preventing the disease, that is, causing the clinical        symptoms of the disease not to develop;    -   (ii) inhibiting the disease, that is, arresting the development        of clinical symptoms; and/or    -   (iii) relieving the disease, that is, causing the regression of        clinical symptoms.

The term “effective amount”, means a dosage sufficient to providetreatment for the disease state being treated. This will vary dependingon the patient, the disease and the treatment being effected.

The term “pharmaceutically acceptable salt” refers to salts derived froma variety of organic and inorganic counter ions well known in the artand include, by way of example only, sodium, potassium, calcium,magnesium, ammonium, tetraalkylammonium, and the like; and when themolecule contains a basic functionality, salts of organic or inorganicacids, such as hydrochloride, hydrobromide, tartarate, mesylate,acetate, maleate, oxalate and the like.

The term “thiol-depleting compound” refers to a compound which uponadministration to a host or to a cell, results in a global lowering ofthe concentration of available reduced thiol (e.g., glutathione).Examples of thiol-depleting compounds include buthionine sulfoximine(“BSO”, a known inhibitor of glutathione synthesis), diethyl maleate (athiol reactive compound) dimethyl fumarate, N-ethyl maleimide, diamide(diazene dicarboxylic acid bis-(N,N′-dimethylamide)) and the like.

The term “ionizing radiation” refers to radiation conventionallyemployed in the treatment of tumors which radiation, either as a largesingle dosage or as repeated smaller dosages, will initiate ionizationof water thereby forming reactive oxygen species. Ionizing radiationincludes, by way of example, x-rays, electron beams, γ-rays, and thelike.

The term “oxalate” salts represents a dianion of oxalic acid, includingits salts. Illustrative examples of oxalic acid salts include theirsodium, potassium and ammonium salts. The term “oxalate precursors”represents compounds which undergo a chemical transformation (in thepresence of a texaphyrin) to form the oxalic acid dianion, i.e., O₂CCO₂²⁻. Illustrative examples of oxalate precursors are oxalic acid esters,oxalic acid diesters, ascorbate, dehydroascorbate, glyoxal, oxamates,oxamide(s), glycolates, and oxalyl chloride. It is understood that thepreceding oxalate precursors, especially acids, can exist as theircorresponding salts such as sodium, potassium and ammonium salts.

The term “porphyrin derivative” refers to those molecules which containas part of their chemical structure a polypyrrole macrocycle.

The term “DNA alkylators” refer to well known alkylating agents whichalkylate DNA thereby interfering with cellular processes and leading tocell death. Suitable alkylating agents include nitrogen mustards (e.g.,mechlorethamine, cyclophosphamide, ifosfamide, mephalan, chlorambuciland estramustine), etheleneimines and methylmelamines (e.g.,hexamethylmelamine and thiotepa), alkyl sulfonates (e.g., busulfan),nitroureas (e.g., carmustine, lomusine, semustine, and streptozocin),and triazines (e.g., dacarbazine, procarbazine, and aziridine).

Experimental

Methods

The following examples describe the reaction of GdTex withdehydroascorbic acid in buffered solution to provide the oxalatecoordination complex of the invention, and the reaction of GdTex with(di)sodium oxalate to provide the same product. The cellular uptake ofGdTex in the presence of ascorbate is also described.

General Procedure: General Protocol to Test for Formation of M-TexOxalate Complex in Buffer

To a solution of motexafin gadolinium (131 μM) in 400 μL buffer (100 mMsodium chloride, 50 mM HEPES, pH 7.5) was added a 10-fold molar excessof neat (either solid or liquid) compound being tested as a source ofoxalate. The UV-visible absorbance of the resulting solution was thenmonitored for 24 hours. The following species all resulted in formationof the characteristic absorbances at 510 nm and 780 nm: ascorbic acid,dehydroascorbic acid, oxalic acid, sodium oxalate, dimethyl oxalate,diethyl oxalate, dibutyl oxalate, di-tert-butyl oxalate, glyoxylic acid,glyoxal, oxamic acid, and oxamide (All compounds were purchased fromAldrich Chemical Co., Milwaukee, Wis., except for dehydroascorbic acid,which was obtained in dimeric form from Fluka Chemical Co., Milwaukee,Wis.).

General Description of Formation of M-Tex Oxalate Complexes in Buffer.

A 10 mM stock solution of sodium oxalate (Aldrich Chemical Co.,Milwaukee, Wis.) in water was prepared by dissolving 13.4 mg in 10 mL ofACS grade water. Test solutions of various Texaphyrin metal cationcomplexes at 50 μM concentration in buffer (5 mM HEPES, pH 7.5, 10 mMsodium chloride) and sodium oxalate (1 mM, all concentrations final)were prepared by combining stock sodium oxalate, buffer, and Texaphyrincomplex solutions and adding ACS grade water to 1 mL final volume. Testsolutions were stored in the dark for 24 hours, whereupon the UV-visspectra were measured. Spectra of the following texaphyrins wereobserved to have altered to form new absorbances characteristic ofoxalate complex formation: motexafin europium(III), motexafingadolinium(III), motexafin terbium(III), motexafin dysprosium(III),motexafin holmium(III), motexafin erbium(III), and motexafinlutetium(III). Spectra for all Texaphyrin oxalate complexes displayedabsorbance maxima at 510 nm and 780 nm, regardless of the initialabsorbance wavelengths of the Texaphyrin complex starting materials,which ranged from 474-478 nm and 732-746 nm.

EXAMPLE 1 Reaction of Motexafin Gadolinium (Gd-Tex) with Ascorbic Acidin Buffered Solution

A solution of ascorbic acid (1.23 mM) in 50 mM HEPES buffer, pH 7.5, 100mM NaCl (all concentrations final) was placed in a 1 mm quartz cuvetteat ambient temperature. The UV-visible spectrum of this solution wasrecorded every 30 seconds following addition of a solution of Gd-Tex inACS (American Chemical Society grade) water (62 μM final, 0.05 eq.).Buffer was treated with Chelex 100™ (BioRad Labs, Hercules, Calif.)prior to use, to remove endogenous transition metal cation contaminants.Within an hour after addition of Gd-Tex, the absorbance of ascorbate at266 nm was observed to decrease. Moreover, the absorbance maxima ofGd-Tex at 470 nm and 740 nm were converted to new absorbance maxima at510 nm and 780 nm, corresponding to formation of the oxalatecoordination polymer of Gd-Tex.

EXAMPLE 2 Reaction of Motexafin Gadolinium (Gd-Tex) with DehydroascorbicAcid in Buffered Solution

Motexafin gadolinium (Gd-Tex, 50 mg, 43.6 μmol) was placed in a 50 mLround bottom flask and dissolved at room temperature in ACS grade water(20 mL). Dehydroascorbic acid (DHA, 15.3 mg, 87.9 μmol) (AldrichChemical, Milwaukee, Wis.) was placed in a 15 mL screw-cup vial andbuffer (10 mL, 100 mM NaCl, 50 mM HEPES, pH=7.5) was added. Sonicationfor 10 min at 25° C. produced very fine yellow suspension. Thissuspension was added at once to the above aqueous solution of Gd-Tex andagitated as it was heated to about 50° C. using a water bath underambient atmosphere. Progress of the reaction was followed by monitoringthe increased absorbance in the UV-visible spectrum at 780 nm. Afterabout 75 minutes, and after no further changes in the spectrum wereobserved, another portion of solid DHA (15.3 mg, 87.9 μmol) was added tothe reaction mixture, and the resulting reaction mixture was agitatedfor about 18 h. The reaction was judged to be complete as evidenced bythe complete conversion of the Q-like absorbance band from 740 nm to 780nm. Within several hours upon cooling to ambient temperature, a veryfine dark-brown precipitate was observed in the reaction flask. Thisprecipitate was isolated by centrifugation at 10° C. and 15,000 r.p.m.for 25 min and removal of supernatent. The pellet was resuspended andcentrifuged with ACS grade (×5) to remove salts and other impurities,and then dried under vacuum at 50° C. for 4 days.

Elemental Analysis: Anal. Calcd. for [C₄₈H₆₆N₅O₁₀Gd](C₂O₄)(H₂O): C,52.85; H, 6.03; N, 6.16, Gd, 13.84. Found: C, 52.47; H, 6.01; N, 5.65;Gd, 12.33.

Elemental analysis is based on a 1:1 ratio of the componentsrepresenting structural units “A” and “B” in the coordination polymer.

EXAMPLE 3 Reaction of Motexafin Gadolinium with Sodium Oxalate inAqueous Solution

Motexafin gadolinium (200 mg, 174 μmol) was placed into a 250 mLErlenmeyer flask and dissolved in ACS grade water (50 mL). Sodiumoxalate (233 mg, 1.74 mmol) was dissolved in ACS grade water (10 mL) ina vial, and then added drop wise over 5 minutes to the above solution ofGd-Tex. The reaction mixture, which immediately changed color fromdeep-green to brown, was allowed to stir for about an hour. Theresulting suspension was divided into 4 polypropylene tubes andcentrifuged at 15,000 r.p.m. for 2 hours. The pellet was resuspended andcentrifuged with ACS grade water five times to remove salts and otherimpurities, and then dried under vacuum at 50° C. for 4 days to providethe oxalate complex of Gd-Tex as a brown-green powder (70 mg). TheUV-visible absorbance spectrum indicated complete conversion of theQ-like absorbance band from 740 nm to 780 nm.

Elemental Analysis: Anal. Calcd. for [C₄₈H₆₆N₅O₁₀Gd](C₂O₄)(H₂O)₂: C,52.85; H, 6.03; N, 6.16, Gd, 13.84. Found: C, 51.00; H, 6.04; N, 6.13;Gd, 13.04.

Elemental analysis is based on a 1:1 ratio of the componentsrepresenting structural units “A” and “B” in the coordination polymer.

This procedure was repeated using oxalic-¹³C₂ acid dihydrate (Aldrich)in buffer. The ¹³C NMR spectrum on the resulting material contained aresonance at δ 213.6 (singlet). This singlet indicates that carbon fromthe labeled oxalate is incorporated into the Gd-Tex oxalate complex(coordination polymer), and is in a symmetrical environment.

The following structures represent a turmeric form of the coordinationpolymer of the present invention:

EXAMPLE 4 Formation of a Copolymer Comprised of Gd-Tex and Lu-Tex andOxalate in Buffer

A 10 mM stock solution of sodium oxalate (Aldrich Chemical Co.,Milwaukee, Wis.) in water was prepared by dissolving 13.4 mg in 10 mL ofACS grade water. A mixture of Gd-Tex and Lu-Tex at 50 μM concentrationeach in buffer (50 mM HEPES, pH 7.5, 100 mM sodium chloride, allconcentrations final) was prepared by adding stock texaphyrin complexsolutions to buffer and adding ACS grade water to 900 μL final volume.The resulting mixture was agitated by vortexing to form a homogeneoussolution and allowed to stand at ambient temperature for 5 minutes,whereupon an aliquot of sodium oxalate stock solution (100 μL, 1 mMfinal concentration) was added to the texaphyrin solution, which wasagain agitated by vortexing. This solution was stored in the dark for 10minutes, whereupon the UV-vis spectrum was measured. The spectrum wasobserved to have altered to form new absorbance maxima characteristic ofoxalate complex formation at 510 nm and 780 nm, accompanied by the lossof the initial absorbance wavelength maxima of the Gd-Tex and Lu-Texstarting materials (at ca. 468 and 737 nm, measured prior to oxalateaddition).

EXAMPLE 5 Stability of the 780 nm Species in Human Serum

The stability of the 780 nm species in human serum was tested by adding0.11 mg of the 780 nm species to 0.7 mL of blank human serum in apolystyrene container. The sample was agitated vigorously to facilitatedissolution of solids. When it appeared that the majority of thematerial was in solution, a small volume was transferred to a 1 mmQuartz cuvette and UV-vis scans were performed periodically for 7 hours.The cuvette was maintained at 37° C. in a humidified incubator under a5% CO₂ atmosphere between scans. UV-vis spectra were obtained. Themajority of 780 nm species was still present after 7 hours, indicatingthat the coordination polymer was intact.

EXAMPLE 6 Determination of Absorption of GdTex and LuTex

The absorption of GdTex and LuTex, using different sources of therespective texaphyrin, in HepG2 cells was determined, by comparingabsorption for GdTex and LuTex in the cell line in medium alone, inmedium containing ascorbic acid, and using GdTex and LuTex that had beenpremixed with ascorbate for a period of time before exposure to the cellline.

Materials

-   Pipettes-   DI water-   pH paper (EM Reagents)-   L-Ascorbic Acid (Sigma)-   Motexafin Gadolinium Injection (2 mM in 5% mannitol)-   Motexafin Lutetium Injection (2 mg/mL in 5% mannitol)-   Catalase Roche Molecular Biochemicals, Indianapolis, Ind., 260,000    unit/ml))-   2.5 mM ascorbic acid in water-   5% Mannitol-   Balance: Mettler AT201-   1.5 ml polypropyline centrifuge tubes (VWR Scientific, San    Francisco, Calif.)-   NUNC 4.5 ml cryotubes (VWR)-   15 mL polypropylene centrifuge tubes (VWR)    Cell Line

The HepG2 tumor cell line, a hepatocellular carcinoma, was obtained fromthe American Type Culture Collection (ATCC), Manassas, Va. (Catalog#HB-8065). The HepG2 cells were maintained in Eagle's Minimal Essentialmedium with Earl's BSS and 2 mM L-glutamine (EMEM) that is modified byATCC to contain 1.0 mM sodium pyruvate, 0.1 mM nonessential amino acids,and 1.5 g/L sodium bicarbonate (ATCC, Cat. #30-2003) and supplementedwith 10% fetal bovine serum (FBS) FBS (Hyclone, Logan, Utah, Lot#AHF8559) and 100 U penicillin/100 ug/ml streptomycin (Sigma, St. Louis,Mo.). Cells are fed one to two times weekly and passed at 3,000,000cells per 75 cm tissue culture flask (Costar). Cells are passed using0.25% trypsin, 0.02% EDTA solution (50/50 PBS/trypsin (Sigma)). Cellsused were at the 96th passage at the time of use.

Methods

GdTex Cell Association Study

HepG2 Cells were plated at a density of 500,000 cells per dish in 100 mmtissue culture dishes containing 10 mL of RPMI media (Gibco, Rockville,Md.) supplemented with 10% Fetal Bovine Serum (Lot#AJC9908, and 100 U/mLpenicillin/100 ug/mL streptomycin (Lot #50K2308, Sigma, St. Louis, Mo.).Cells were plated out 1-2 days prior to treating with motexafingadolinium.

The day prior to treating the dishes with GdTex (9-19-00), an “aged”solution was prepared containing 50 μM GdTex, 100 μM ascorbate, andCatalase (at a concentration 1:1000 of the stock solution concentrationprovided by the vendor). This solution was incubated at 37° C. 5% CO₂for approximately 24 hr prior to addition to the appropriate testdishes.

On the day of treatment, test solutions were prepared as shown in theTable I below in pre-incubated medium. The pre-incubated medium wasequilibrated at 37° C. in 5% CO₂ for at least 1 hour prior to use formaking each test solution. To the pre-equilibrated medium, the catalasewas added first (if indicated) and mixed, then the ascorbate (ifindicated) was added and mixed. The GdTex (if indicated) was added lastfollowed by a final mix. Within one hour of preparation, the medium wasremoved from each dish are replaced with 10 mL of appropriate testsolution. Each condition was tested in three replicate dishes, exceptfor the no-cells controls, for which 2 dishes were used. No-cellcontrols were prepared by adding 10 mL of the appropriate solution to anempty dish that did not contain any cells. TABLE I Vol. Vol. Vol. 5% 2mM Vol. 10X Vol. Total GdTex Asc. Cat. Mannitol GdTex- Asc. Cat. RPMIVol. Conc. Conc. Conc. Test Article (mL) (mL) (mL) (mL) (mL) (mL) (μM)(μM) (X) Control 3 N/A 4.8 12 100.20 120 0 100 1 Gd-Tex 3 N/A N/A 117.0120 50 0 0 Gd-Tex + Asc 3 4.8 N/A 112.2 120 50 100 0 Gd- 3 4.8 12 100.2120 50 100 1 Tex + Asc + Catalase Gd- 3 4.8 12 100.2 120 50 100 1 Tex +Asc + Catalase (aged)LuTex Cell Association Study

HepG2 Cells were plated at a density of 500,000 cells per dish in 100 mmtissue culture dishes containing 10 mL of RPMI media (Gibco, Rockville,Md.) supplemented with 10% Fetal Bovine Serum (Lot#AJC9908, and 100 U/mLpenicillin/100 ug/mL streptomycin (Lot #50K2308, Sigma, St. Louis, Mo.).Cells were plated out 1-2 days prior to treatment with motexafingadolinium.

The day prior to treating the dishes with LuTex, two “aged” solutionswere prepared as shown in Table II below. These two solutions wereincubated at 37° C. in 5% CO₂ for approximately 23 hr prior to additionto the appropriate test dishes. TABLE II Vol. Vol. Vol. Vol. 2 mg/mL 2.5mM 10X Vol. RP Total LuTex Asc. Cat. 5% Mannitol LuTex Asc. Cat. MI Vol.Conc.. Conc Conc Test Article (mL) (mL) (mL) (mL) (mL) (mL) (μM) (μM)(X) Lu-Tex + Catalase N/A 3.5 N/A 12 104.5 120 50 0 1 (aged) Lu- N/A 3.54.8 12 99.7 120 50 100 1 Tex + Asc + Catalase (aged)

On the day of treatment, test solutions were prepared as shown in TableIII below in pre-incubated media. The pre-incubated median wasequilibrated at 37° C. in 5% CO₂ for at least 1 hour prior to use formaking each test solution. To the pre-equilibrated media, the catalasewas added first (if indicated) and mixed, then the ascorbate (ifindicated) was added and mixed. The LuTex (if indicated) was added lastfollowed by a final mix. Within 30 min of preparation, the media wasremoved from each dish replaced with 10 mL of appropriate test solution.Each condition was tested in three replicate dishes, except for theno-cells controls, for which 2 dishes were used. No-cell controls wereprepared by adding 10 mL of the appropriate spiking solution to an emptydish that did not contain any cells. TABLE III 10X Vol. RP Total Lu- 5%Mannitol Lu-Tex Asc. Cat. MI Vol. Tex Cat. Conc Test Article (mL) (mL)(mL) (mL) (mL) (mL) Conc. Asc. Conc. (X) Ctrl 3.5 N/A 4.8 12 99.7 120 0100 1 Lu-Tex 3.5 N/A N/A 116.5 120 50 0 0 Lu-Tex + Asc 3.5 4.8 N/A 111.7120 50 100 0 Lu- 3.5 4.8 12 99.7 120 50 100 1 Tex + Asc + Cat Lu-Tex +Catalase 3.5 4.8 12 99.7 120 50 100 1 (aged) Lu-Tex + ASC + Catalase 3.54.8 12 99.7 120 50 100 1 (aged)Cell Harvesting and AnalysisGdTex Cell Association Study

At the end of the four hour incubation period, four 1 mL samples of testsolution were aliquoted into four microcentrifuge tubes for furtheranalysis. The test solution was then completely aspirated from eachdish, and then each dish was rinsed 3 times with 10 mL PBS. Afteraspirating the final 10 mL rinse, one mL PBS was added to each dish anda sterile cell scraper was used to release the cells from the dish. Theamount of time between the start of washing and completion of thescraping process was approximately 1 hour. Because the cells tended tofloat, it was necessary to use multiple PBS washes (e.g. 5 to 10 smallvolumes) in order to transfer all of the cells into a 15 mLpolypropylene centrifuge tube (Labeled as TUBE 1). TUBE 1 was brought toa final volume of 15 mL and then centrifuged at 23° C. for 10 min @3800rpm using a Beckman GH-38 rotor. The supernatant was poured off and thecell pellet was resuspended in 1 ml of PBS (still in TUBE 1) bypipetting up and down. Additional PBS was added to bring the finalvolume to 10 mL. Centrifugation was repeated using the same conditionsspecified above, and the supernatant was decanted. The cell pellet wasresuspended in 1 mL of PBS by pipeting up and down.

The pellet was then transferred to a fresh 15 mL polypropylenecentrifuge tube (TUBE 2). A second 1 mL of PBS was added to TUBE 1,pipetted up and down, and then transferred to TUBE 2 using a fresh tip.Eight mL of PBS was then added to TUBE 2 to bring the final volume to 10mL. TUBE 2 was centrifuged at 23° C for 10 min at 3800 rpm using aBeckman GH-38 rotor. The pellet was suspended in 0.5 mL of PBS and thevolume transferred to a 6 mL disposable polypropylene test tube (TUBE3). A second 0.5 mL volume of PBS was added to TUBE 2, and thentransferred to TUBE 3 (using a fresh tip) to complete the transfer. Thefinal cell suspension (TUBE 3) was placed in storage at −80° C. forstorage until the time of analysis.

For the t=4 hours dishes, all steps were done as indicated above.However, for the t=0 dishes, all steps were done as described above,except the transfer to TUBE 2 and subsequent 10 mL wash was not done.The transfer to Tube 1 (in 15 mL PBS), centrifugation, decanting, and 10mL wash were all done in TUBE 1 as described above. However, afterdecanting after the. 10 mL wash, the cell pellet was transferreddirectly from TUBE 1 to TUBE 3 for final analysis using two 0.5 mLrinses. When transferring cells, a fresh tip was used for adding thePBS, whereas the original pipette tip was used for actually transferringthe cells to the next tube.

LuTex Cell Association Study

At the end of the four hour incubation period, four 1 mL samples of testsolution were aliquoted into four microcentrifuge tubes for furtheranalysis. The test solution was then completely aspirated from eachdish, and then each dish was rinsed 3 times with 10 mL PBS. Afteraspirating the final 10 mL rinse, one mL PBS was added to each dish anda sterile cell scraper was used to release the cells from the dish. Theamount of time between the start of washing and completion of thescraping process was approximately 1 hour. Because the cells tended tofloat, it was necessary to use multiple PBS washes (e.g. 5 to 10 smallvolumes) in order to transfer all of the cells into a 15 mLpolypropylene centrifuge tube (Labeled as TUBE 1). TUBE 1 was brought toa final volume of 15 mL PBS and then centrifuged at 23° C. for 10 min at3800 rpm using a Beckman GH-38 rotor. The supernatant was poured off andthe cell pellet was resuspended in 1 mL of PBS (still in TUBE 1). Thepipette tip used for resuspending the cells was rinsed two times bypipetting two 1 mL volumes of PBS into the open end of the tip andcollecting the rinse into TUBE 1. Additional PBS was added to bring thefinal volume to 10 mL. Centrifugation was repeated using the same,conditions specified above, and the supernatant was decanted.

The cell pellet was then resuspended in 1 mL of PBS by pipetting up anddown. The pellet was then transferred to a fresh 15 mL polypropylenecentrifuge tube (TUBE 2). A second 1 mL of PBS was added to TUBE 1,pipetted up and down, and then transferred to TUBE 2 using the originaltip. An additional 1 mL wash was done in an identical manner, andfinally, a third 1 mL PBS volume was added to the open end of theoriginal tip and collected into TUBE 2. PBS was then added to TUBE 2 tobring the final volume to 10 mL. TUBE 2 was centrifuged at 23° C. for 10min at 3800 rpm using a Beckman GH-38 rotor. The pellet was suspended in0.25 mL of PBS and the volume transferred to a 6 mL disposablepolypropylene test tube (TUBE 3). Two more rinses of TUBE 2 were done,each using 0.25 mL of PBS with transfers done using the original tip.Therefore, the final volume in TUBE 3 was approximately 0.75 mL. Thefinal cell suspension (TUBE 3) was placed in storage at −80° C. forstorage until the time of analysis. When transferring cells, a fresh tipwas used for adding the PBS, whereas the original pipette tip was usedfor actually transferring the cells to the next tube.

Results

Four hours after incubation, a sample of the supernatant was removedfrom selected dishes and a UV-vis spectrum taken. The percentage of drugthat had precipitated. for each condition was estimated by comparing theabsorbance at 740 nm in the each group with that obtained for the groupspiked with GdTex alone. A visible pellet was only observed for theGdTex+ascorbate+catalase (aged) group. Based on the decrease inabsorbance at 740 nm, the percentage precipitated for this group wasestimated to be 60-63% over the 4 hour period of the study.

A similar analysis was performed for the spiking solutions used in theLuTex study. A visible pellet was only observed for the LuTex+catalase(aged) and the LuTex+ascorbate+catalase (aged) groups. Based on thedecrease in absorbance at 730 nm, the percentage precipitated for theLuTex+ascorbate+catalase (aged) group was estimated to be 24-31% overthe 4 hr period of the study.

UV-Vis spectra were obtained in order to determine if a 780 nm absorbingspecies was present in the spiking solutions as part of the GdTex cellassociation study. 780 nm absorbing species was present both at the timeof spiking and after four hours in the GdTex+ascorbate+catalase (aged)group. However, this species was reduced after centrifugation at16,000×g for 30 minutes, suggesting that a significant percentage of the780 nm absorbing material was present as a precipitate. Similar resultswere obtained for the LuTex cell association study. Interestingly, the780 nm species was not observed for the LuTex+catalase (aged) group eventhough a small pellet was visible after centrifugation. This resultsuggests that the precipitate formed in this solution may have adifferent composition than that seen in the LuTex+ascorbate+catalase(aged) group. Alternatively, the amount of precipitate may have been toosmall to generate significant absorbance at 780 nm. However, it wasnoted that the final cell pellets obtained in PBS for these two groupswere different shades of color (reddish brown and greenish black,respectively), suggesting that the composition of the precipitate mayhave been different between the two groups.

UV-vis spectra obtained of the cell pellets in the GdTex study,resuspended in PBS, showed that significant absorbance in the 700-850 nmregion of the spectrum was seen only for the GdTex+ascorbate+catalase(aged) group. This was consistent with the fact that there wasrelatively little cell association in the other groups. Furthermore, thespectra suggested that the majority of the material associated with thecells was the 780 nm absorbing material. Similar results were obtainedin the LuTex study, except both 730 and 780 nm absorbing species wereobserved in the LuTex+ascorbate+catalase (aged) group.

Shown by these experiments is that GdTex association with HepG2 cellswas smaller that corresponding LuTex cell association with this cellline in the absence of ascorbate. However, for freshly preparedsolutions made in the presence of ascorbate, GdTex and LuTex showedcomparable levels of association. For the aged solutions, theGdTex+ascorbate+catalase (aged) group showed much greater uptakecompared to the LuTex+ascorbate+catalase (aged) group.

EXAMPLE 5 Cellular Uptake of Gd-Tex Oxalate Complex in vitro

Human uterine cancer cell line MES-SA cells (Harker W G, MacKintosh F R,Sikic B I Cancer Res 1983;43:4943-4950) were allowed to adhere to a96-well microtiter plate (20,000 cells per well) overnight in 180 μLMcCoys 5A medium supplemented with 10% fetal bovine serum. Stock sodiumoxalate (Aldrich Chemical, St. Louis, Mo., 1.0 mM in medium, 90 μL) wasserially diluted (1:3) in rows B through F (discarding the final 90 μL).Row G was used for no-oxalate control. Stock solutions of Gd-Tex (2 mMin water) diluted in medium were prepared and added to the plates togive a final volume of 200 μL in all wells. Columns 2 and 3 contained100 μM Gd-Tex; columns 4-7 contained 75 μM Gd-Tex, columns 8 and 9contained 25 μM Gd-Tex; and columns 10 and 11 contained no Gd-Tex (allconcentrations final). The plates were incubated at 37° C. under a 5%CO₂/95% air atmosphere. Complex-containing medium was exchanged forfresh medium after 49 hours, whereupon medium was removed and cells werewashed with phosphate buffered saline (180 μL). Phosphate bufferedsaline (supplemented with 10 mM KCl, 1 mM MgCl₂, 1 mM CaCl₂ and 20 mMglucose, 100 μL) was added to the plate and the absorbance was measuredusing a plate reader (VMax, Molecular Devices) at 510 nm-650 nm.

In a separate experiment, MES-SA cells (20,000 cells/well) were platedin a 96-well plate and allowed to adhere overnight in 180 μL McCoys 5Amedium supplemented with 10% fetal bovine serum. Stock sodium oxalate(1.0 mM in medium (90 μL) was serially diluted (1:3) in rows B through F(discarding the final 90 μL). Row G was used for no-oxalate control.Stock solutions of Gd-Tex (2 mM in water) diluted in medium wereprepared and added to the plates to give a final volume of 200 μL in allwells. Columns 2 and 3 contained 50 μM Gd-Tex; columns 4-5 contained37.5 μM Gd-Tex, columns 6-7 contained 25 μM Gd-Tex, columns 8 and 9contained 12.5 μM Gd-Tex; and columns 10 and 11 contained no Gd-Tex (allconcentrations final). The plates were incubated at 37° C. under a 5%CO_(2/95)% air atmosphere. Complex-containing medium was exchanged forfresh medium after 24 hours, whereupon medium was removed and cells werewashed with phosphate buffered saline (180 μL). Dichlorofluorescinacetate (DCFA, 5 μg/mL, Sigma Chemical, St. Louis, Mo.) in phosphatebuffered saline (supplemented with 10 mM KCl, 1 mM MgCl₂, 1 mM CaCl₂ and20 mM glucose, 100 μL) was added to the plate and the plate was returnedto the incubator for 13 hours. The fluorescence was measured using afluorescent plate reader (Fluoroskan, LabSystems, Inc.) using 485 nmexcitation and 538 nm emission wavelengths (Rosenkranz A R, SchmaldienstS, Stuhlmeier K M, et al. J Immunol Meth 1992;156:39-45).

Incubating cells in the presence of both Gd-Tex and oxalate resulted incell uptake of Gd-Tex oxalate complex, as evidenced by the increasedabsorbance due to the drug at 510-650 nm. Under similar conditions, adichloroflorescein fluorescence was observed which was proportional toconcentrations of oxalate and Gd-Tex in the medium. These resultsdemonstrate that cellular uptake of Gd-Tex oxalate complex is morefacile than the uptake of Gd-Tex, and that the compound thus taken up bycells may indirectly be measured by a corresponding increase indichlorofluorescin oxidation, or directly by its absorbance at 510-650nm.

EXAMPLE 6 The Cellular Uptake of the Gadolinium(III) Complex ofTexaphyrin in the Presence of Ascorbate and Gd-Tex Oxalate Complex(Coordination Polymer)

Human lung cancer cells A549 were plated in 5 cm petri dishes in RPMI1640 medium containing 15% fetal bovine serum and allowed to grow until60% confluent. Cultures were then treated for 19 hours with: 1. Nothing(Control group). 2. 50 M Gd-Tex. 3. 50 M Gd-Tex and 60 M ascorbate. 4.50 M Gd-Tex for 16 hours, followed by 50 M Gd-Tex oxalate complex for 3hours. Cultures were washed twice with Dulbecco's phosphate bufferedsaline and then incubated in Hank's buffered saline solution containingeither no dichlorofluorescin acetate (DCFA, Sigma Chemical) or 5 μg/mLdichlorofluorescin acetate for 10 minutes at 37° C. Cultures weretreated with trypsin for 5 minutes to form a single cell suspension, andanalyzed using a flow cytometer (Becton-Dickenson) within 20 minutes.

The results are shown in FIGS. 4 and 5. The fluorescence in channel FL3(>650 nm, FIG. 4) corresponds to fluorescence derived from Gd-Tex. TheGd-Tex-oxalate complex is relatively non-fluorescent (as compared toGd-Tex) and so there appears to be similar uptake of Gd-Tex in theGd-Tex and Gd-Tex plus ascorbate groups. However, the enhancedfluorescence seen in the culture treated with Gd-Tex oxalate complexindicates that dissociation back to free (i.e., fluorescent) Gd-Tex canoccur within the cell or that there is sufficient uptake of this speciesto give rise to the greater fluorescence signal despite its lowerfluorescent quantum yield. The fluorescence in channel FL1 (530±15 nm,FIG. 5) corresponds to fluorescence from dichlorofluorescin, producedupon intracellular oxidation of DCFA. In this figure, enhanced uptake ingroups treated with Gd-Tex in the presence of ascorbate, and pre-formedGd-Tex oxalate complex, is seen indirectly via the greater oxidativestress produced in these groups, relative to cultures treated withGd-Tex alone.

Utility, Testing and Administration

General Utility

The compounds of the present invention are effective in the treatment ofconditions known to respond to metallotexaphyrin therapy, includingdiseases characterized by neoplastic tissue, (e.g. the cancers sarcoma,lymphoma, leukemia, carcinoma, brain metastases, glioma, glioblastoma,cancer of the prostate, melanoma, and the like), cardiovascular diseases(e.g., atherosclerosis, intimal hyperplasia and restenosis) and otheractivated macrophage-related disorders including autoimmune diseases(e.g., rheumatoid arthritis, Sjogrens, scleroderma, systemic lupuserythematosus, non-specific vasculitis, Kawasaki's disease, psoriasis,Type I diabetes, pemphigus vulgaris, multiple sclerosis), granulomatousdiseases (e.g., tuberculosis, sarcoidosis, lymphomatoid granulomatosis,Wegener's granulomatosus), inflammatory diseases (e.g., inflammatorylung diseases such as interstitial pneumonitis and asthma, inflammatorybowel disease such as Crohn's disease, and inflammatory arthritis), intransplant rejection (e.g., in heart/lung transplants) and in ophthalmicdiseases that result from undesired neovascularization , in particularage-related macular degeneration.

Testing

Activity testing is conducted as described in those patents and patentapplications incorporated by reference above, and in the followingreferences, and by modifications thereof. The compounds of the inventionhave been shown to have various in vitro and in vivo activity. See, forexample, Young et al., Methods for Cancer Chemosensitization, and U.S.Pat. No. 5,776,925.

Pharmaceutical Compositions

The compounds of the present invention are usually administered in theform of pharmaceutical compositions. This invention therefore providespharmaceutical compositions that contain, as the active ingredient, oneor more of the compounds (coordination polymer) of the presentinvention, or a pharmaceutically acceptable salt thereof, and one ormore pharmaceutically acceptable excipients, carriers, including inertsolid diluents and fillers, diluents, including sterile aqueous solutionand various organic solvents, permeation enhancers, solubilizers andadjuvants. The compounds may be administered alone or in combinationwith other therapeutic agents. Such compositions are prepared in amanner well known in the pharmaceutical art (see, e.g., Remington'sPharmaceutical Sciences, Mace Publishing Co., Philadelphia, Pa. 17^(th)Ed. (1985) and “Modem Pharmaceutics”, Marcel Dekker, Inc. 3^(rd) Ed. (G.S. Banker & C. T. Rhodes, Eds.).

Administration

The compounds of the invention may be administered in either single ormultiple doses by any of the accepted modes of administration of agentshaving similar utilities, for example as described in those patents andpatent applications incorporated by reference above, including rectal,buccal, intranasal and transdermal routes, by intra-arterial injection,intravenously, intraperitoneally, parenterally, intramuscularly,subcutaneously, orally, topically, as an inhalant, or via an impregnatedor coated device such as a stent, for example, or an artery-insertedcylindrical polymer, with parenteral and intra-arterial administrationbeing preferred, and intra-arterial being more preferred.

One preferred mode for administration is parental, particularly byinjection. The forms in which the novel compositions of the presentinvention may be incorporated for administration by injection includeaqueous or oil suspensions, or emulsions, with sesame oil, corn oil,cottonseed oil, or peanut oil, as well as elixirs, mannitol, dextrose,or a sterile aqueous solution, and similar pharmaceutical vehicles.Aqueous solutions in saline are also conventionally used for injection,but less preferred in the context of the present. invention. Ethanol,glycerol, propylene glycol, liquid polyethylene glycol, and the like(and suitable mixtures thereof), cyclodextrin derivatives, and vegetableoils may also be employed. The proper fluidity can be maintained, forexample, by the use of a coating, such as lecithin, by the maintenanceof the required particle size in the case of dispersion and by the useof surfactants. The prevention of the action of microorganisms can bebrought about by various antibacterial and antifungal agents, forexample, parables, chlorobutanol, phenol, sorbic acid, thimerosal, andthe like.

Sterile inject able solutions are prepared by incorporating the activecompounds in the required amount in the appropriate solvent with variousother ingredients as enumerated above, as required, followed by filteredsterilization. Generally, dispersions are prepared by incorporating thevarious sterilized active ingredients into a sterile vehicle whichcontains the basic dispersion medium and the required other ingredientsfrom those enumerated above. In the case of sterile powders for thepreparation of sterile inject able solutions, the preferred methods ofpreparation are vacuum-drying and freeze-drying techniques which yield apowder of the active ingredient plus any additional desired ingredientfrom a previously sterile-filtered solution thereof.

Compounds of the invention may be impregnated into a stent by diffusion,for example, or coated onto the stent such as in a gel form, forexample, using procedures known to one of skill in the art in light ofthe present disclosure.

Oral administration is another route for administration of the compoundsof this invention. Preferred is oral administration via capsule orenteric coated tablets, or the like, which prevent degradation of thecompounds of the invention in the stomach. In making the pharmaceuticalcompositions that include at least one compound of the invention, theactive ingredient is usually diluted by an excipient and/or enclosedwithin such a carrier that can be in the form of a capsule, sachet,paper or other container. When the excipient serves as a diluent, in canbe a solid, semi-solid, or liquid material (as above), which acts as avehicle, carrier or medium for the active ingredient. Thus thecompositions can be in the form of tablets, pills, powders, lozenges,sachets, cachets, elixirs, suspensions, emulsions, solutions, syrups,aerosols (as a solid or in a liquid medium), ointments containing, forexample, up to 10% by weight of the active compound, soft and hardgelatin capsules, sterile inject able solutions, and sterile packagedpowders.

Some examples of suitable excipients include lactose, dextrose, sucrose,sorbitol, mannitol, starches, gum acacia, calcium phosphate, alginates,tragacanth, gelatin, calcium silicate, microcrystalline cellulose,polyvinylpyrrolidone, cellulose, sterile water, syrup, and methylcellulose. The formulations can additionally include: lubricating agentssuch as talc, magnesium stearate, and mineral oil; wetting agents;emulsifying and suspending agents; preserving agents such as methyl- andpropylhydroxy-benzoates; sweetening agents; and flavoring agents.

The compositions of the invention can be formulated so as to providequick, sustained or delayed release of the active ingredient afteradministration to the patient by employing procedures known in the art.Controlled release drug delivery systems for oral administration includeosmotic pump systems and dissolutional systems containing polymer-coatedreservoirs or drug-polymer matrix formulations. Examples of controlledrelease systems are given in U.S. Pat. Nos. 3,845,770; 4,326,525;4,902514; and 5,616,345. Another preferred formulation for use in themethods of the present invention employs transdermal delivery devices(“patches”). Such transdermal patches may be used to provide continuousor discontinuous infusion of the compounds of the present invention incontrolled amounts. The construction and use of transdermal patches forthe delivery of pharmaceutical agents is well known in the art. See,e.g., U.S. Pat. Nos. 5,023,252, 4,992,445 and 5,001,139. Such patchesmay be constructed for continuous, pulsatile, or on demand delivery ofpharmaceutical agents.

The compositions are preferably formulated in a unit dosage form. Theterm “unit dosage forms” refers to physically discrete units suitable asunitary dosages for human subjects and other mammals, each unitcontaining a predetermined quantity of active material calculated toproduce the desired therapeutic effect, in association with a suitablepharmaceutical excipient (e.g., a tablet, capsule, ampoule). The activecompound is effective over a wide dosage range and is generallyadministered in a pharmaceutically effective amount. Preferably, fororal administration, each dosage unit contains from 10 mg to 2 g of ancompound of the invention, and for parenteral administration, preferablyfrom 10 to 700 mg of an compound of the invention, preferably about 350mg. It will be understood, however, that the amount of the compoundactually administered will be determined by a physician, in the light ofthe relevant circumstances, including the condition to be treated, thechosen route of administration, the actual compound administered and itsrelative activity, the age, weight, and response of the individualpatient, the severity of the patient's symptoms, and the like.

For preparing solid compositions such as tablets, the principal activeingredient is mixed with a pharmaceutical excipient to form a solidpreformulation composition containing a homogeneous mixture of ancompound of the present invention. When referring to thesepreformulation compositions as homogeneous, it is meant that the activeingredient is dispersed evenly throughout the composition so that thecomposition may be readily subdivided into equally effective unit dosageforms such as tablets, pills and capsules.

The tablets or pills of the present invention may be coated or otherwisecompounded to provide a dosage form affording the advantage of prolongedaction, or to protect from the acid conditions of the stomach. Forexample, the tablet or pill can comprise an inner dosage and an outerdosage component, the latter being in the form of an envelope over theformer. The two components can be separated by an enteric layer thatserves to resist disintegration in the stomach and permit the innercomponent to pass intact into the duodenum or to be delayed in release.A variety of materials can be used for such enteric layers or coatings,such materials including a number of polymeric acids and mixtures ofpolymeric acids with such materials as shellac, cetyl alcohol, andcellulose acetate.

Compositions for inhalation or insufflation include solutions andsuspensions in pharmaceutically acceptable, aqueous or organic solvents,or mixtures thereof, and powders. The liquid or solid compositions maycontain suitable pharmaceutically acceptable excipients as describedsupra. Preferably the compositions are administered by the oral or nasalrespiratory route for local or systemic effect. Compositions inpreferably pharmaceutically acceptable solvents may be nebulized by useof inert gases. Nebulized solutions may be inhaled directly from thenebulizing device or the nebulizing device may be attached to a facemask tent, or intermittent positive pressure breathing machine.Solution, suspension, or powder compositions may be administered,preferably orally or nasally, from devices that deliver the formulationin an appropriate manner.

Dosages

The specific dose will vary depending on the particular compound of theinvention chosen, the dosing regimen to be followed, and the particulartherapeutic energy or agent with which it is administered, employingdosages within the range of about 0.01 mg/kg/treatment up to about 100mg/kg/treatment, preferably about 0.1 mg/kg/treatment to about 50mg/kg/treatment. It will be appreciated by one skilled in the art,however, that there are specific differences in the most effectivedosimetry depending on the apical ligands chosen, because of the widerange of properties available, such as solubilities, lipophilicityproperties, lower toxicity, and improved stability.

Administration for Photodynamic Therapy

By way of example, a compound of Formula I, having lutetium as a metalin the Texaphyrin, may be administered in solution, optionally in 5%mannitol USP. Dosages of about 1.0-2.0 mg/kg to about 4.0-7.0 mg/kg,preferably 3.0 mg/kg, are employed, although in some cases a maximumtolerated dose may be higher, for example about 5 mg/kg. The Texaphyrinis administered by intravenous injection, followed by a waiting periodof from as short a time as several minutes or about 3 hours to as longas about 72 or 96 hours (depending on the treatment being effected) tofacilitate intracellular uptake and clearance from the plasma andextracellular matrix prior to the administration of photoirradiation.

Dose levels for certain uses may range from about 0.05 mg/kg to about 20mg/kg administered in single or multiple doses (e.g. before eachfraction of radiation). The lower dosage range would be preferred forintra-arterial injection or for impregnated stents.

The optimum length of time following administration of an compound ofthe invention until light treatment can vary depending on the mode ofadministration, the form of administration, and the type of targettissue. Typically, the compound of the invention persists for a periodof minutes to hours, depending on the compound of the invention, theformulation, the dose, the infusion rate, as well as the type of tissueand tissue size.

When employing photodynamic therapy, a target area is treated with lightat about 780±16.5 nm. After the photosensitizing compound of theinvention has been administered, the tissue being treated is photoirradiated at a wavelength similar to the absorbance of the compound ofthe invention, usually either about 440-540 nm or about 740-840 nm, morepreferably about 490-540 nm or about 750-800 nm, or most preferablyabout 450-500 nm or about 765-780 nm. The light source may be a laser, alight-emitting diode, or filtered light from, for example, a xenon lamp;and the light may be administered topically, endoscopically, orinterstitially (via, e.g., a fiber optic probe), or intra arterially.Preferably, the light is administered using a slit-lamp delivery system.The fluence and irradiance during the photo irradiating treatment canvary depending on type of tissue, depth of target tissue, and the amountof overlying fluid or blood. For example, a total light energy of about100 J/cm² can be delivered at a power of 200 mW to 250 mW, dependingupon the target tissue.

Compounds of the invention may be administered before, at the same time,or after administration of one or more chemotherapeutic drugs. Thecompound of the invention may be administered as a single dose, or itmay be administered as two or more doses separated by an interval oftime. The compound of the invention may be administered concurrentlywith, or from about one minute to about 12 hours following,administration of a chemotherapeutic drug, preferably from about 5 minto about 5 hr, more preferably about 4 to 5 hr. The dosing protocol maybe repeated, from one to three times, for example. A time frame that hasbeen successful in vivo is administration of an compound of theinvention about 5 min and about 5 hr after administration of achemotherapeutic agent, with the protocol being performed once per weekfor three weeks. Administration may be intra-arterial injection,intravenous, intraperitoneal, intramuscular, subcutaneous, oral,topical, or via a device such as a stent, for example, with parenteraland intra-arterial administration being preferred, and intra-arterialbeing more preferred.

Administering a compound of the invention and a chemotherapeutic drug tothe subject may be prior to, concurrent with, or following vascularintervention. The method may begin at a time roughly accompanying avascular intervention, such as an angioplastic procedure, for example.Multiple or single treatments prior to, at the time of, or subsequent tothe procedure rnay be used. “Roughly accompanying a vascularintervention” refers to a time period within the ambit of the effects ofthe vascular intervention. Typically, an initial dose of an compound ofthe invention and chemotherapeutic drug will be within 6-12 hours of thevascular intervention, preferably within 6 hours thereafter. Follow-updosages may be made at weekly, biweekly, or monthly intervals. Design ofparticular protocols depends on the individual subject, the condition ofthe subject, the design of dosage levels, and the judgment of theattending practitioner.

Administration for Radiation Sensitization

Compounds of the invention where the metal is gadolinium are typicallyadministered in a solution containing 2 mM optionally in 5% mannitolUSP/water (sterile and non-pyrogenic solution). Dosages of 0.1 mg/kg upto as high as about 29.0 mg/kg have been delivered, preferably about 3.0to about 15.0 mg/kg (for volume of about 90 to 450 mL) may be employed,optionally with pre-medication using anti-emetics when dosing aboveabout 6.0 mg/kg. The compound is administered via intravenous injectionover about a 5 to 10 minute period, followed by a waiting period ofabout 2 to 5 hours to facilitate intracellular uptake and clearance fromthe plasma and extracellular matrix prior to the administration ofradiation.

When employing whole brain radiation therapy, a course of 30 Gy in ten(10) fractions of radiation may be administered over consecutive daysexcluding weekends and holidays. In the treatment of brain metastases,whole brain megavolt radiation therapy is delivered with ⁶⁰Coteletherapy or a ≧4 MV linear accelerator with isocenter distances of atleast 80 cm, using isocentric techniques, opposed lateral fields andexclusion of the eyes. A minimum dose rate at the midplane in the brainon the central axis is about 0.5 Gy/minute.

Compounds of the invention used as radiation sensitizers may beadministered before, or at the same time as, or after administration ofthe ionizing radiation. The compound of the invention may beadministered as a single dose, as an infusion, or it may be administeredas two or more doses separated by an interval of time. Where thecompound of the invention is administered as two or more doses, the timeinterval between the compound of the invention administrations may befrom about one minute to a number of days, preferably from about 5 minto about 1 day, more preferably about 4 to 5 hr. The dosing protocol maybe repeated, from one to ten or more times, for example. Dose levels forradiation sensitization may range from about 0.05 mg/kg to about 20mg/kg administered in single or multiple doses (e.g. before eachfraction of radiation). The lower dosage range would be preferred forintra-arterial injection or for impregnated stents.

Administration may be intra-arterial injection, intravenous,intraperitoneal, intramuscular, subcutaneous, oral, topical, or via animpregnated or coated device such as a stent, for example, or anartery-inserted cylindrical polymer, with intravenous and intra-arterialadministration being preferred, and intra-arterial being more preferred.In one aspect of the invention, a patient H restenosis or at risk forrestenosis is administered a dose of compound of the invention atintervals with each dose of radiation.

Administering a compound of the invention to the subject may be priorto, concurrent with, or following vascular intervention, and theintervention is followed by radiation. The method may begin prior to,such as about 24-48 hours prior to, or at a time roughly accompanyingvascular intervention, for example. Multiple or single treatments priorto, at the time of, or subsequent to the procedure may be used. “Roughlyaccompanying the vascular intervention” refers to a time period withinthe ambit of the effects of the vascular intervention. Typically, aninitial dose of compound of the invention and radiation will be within1-24 hours of the vascular intervention, preferably within about 5-24hours thereafter. Follow-up dosages may be made at weekly, biweekly, ormonthly intervals. Design of particular protocols depends on theindividual subject, the condition of the subject, the design of dosagelevels, and the judgment of the attending practitioner.

Administration for Sonodynamic Therapy

The use of texaphyrins in sonodynamic therapy is described in U.S.patent application Ser. No. 09/111,148, which is incorporated herein byreference. Texaphyrin is administered before administration of theultrasound. The Texaphyrin may be administered as a single dose, or itmay be administered as two or more doses separated by an interval oftime. Parenteral administration is typical, including by intravenous andinterarterial injection. Other common routes of administration can alsobe employed.

Ultrasound is generated by a focused array transducer driven by a poweramplifier. The transducer can vary in diameter and spherical curvatureto allow for variation of the focus of the ultrasonic output.Commercially available therapeutic ultrasound devices may be employed inthe practice of the invention. The duration and wave frequency,including the type of wave employed may vary, and the preferred durationof treatment will vary from case to case within the judgment of thetreating physician. Both progressive wave mode patterns and standingwave patterns have been successful in producing cavitation of diseasedtissue. When using progressive waves, the second harmonic canadvantageously be superimposed onto the fundamental wave.

Preferred types of ultrasound employed in the present invention areultrasound of low intensity, non-thermal ultrasound, i.e., ultrasoundgenerated within the wavelengths of about 0.1 MHz and 5.0 MHz and atintensities between about 3.0 and 5.0 W/cm².

Utility

Pharmaceutical Formulations

The following formulation examples illustrate representativepharmaceutical compositions of the present invention.

FORMULATION EXAMPLE 1

Hard gelatin capsules containing the following ingredients are prepared:Quantity Ingredient (mg/capsule) Active Ingredient 30.0 Starch 305.0Magnesium stearate 5.0

The above ingredients are mixed and filled into hard gelatin capsules in340 mg quantities.

FORMULATION EXAMPLE 2

A tablet formula is prepared using the ingredients below: QuantityIngredient (mg/tablet) Active Ingredient 25.0 Cellulose,microcrystalline 200.0 Colloidal silicon dioxide 10.0 Stearic acid 5.0

The components are blended and compressed to form tablets, each weighing240 mg.

FORMULATION EXAMPLE 3

Tablets, each containing 30 mg of active ingredient, are prepared asfollows: Quantity Ingredient (mg/tablet) Active Ingredient 30.0 mgStarch 45.0 mg Microcrystalline cellulose 35.0 mg Polyvinylpyrrolidone 4.0 mg (as 10% solution in sterile water) Sodium carboxymethyl starch 4.5 mg Magnesium stearate  0.5 mg Talc  1.0 mg Total  120 mg

The active ingredient, starch and cellulose are passed through a No. 20mesh U.S. sieve and mixed thoroughly. The solution ofpolyvinylpyrrolidone is mixed with the resultant powders, which are thenpassed through a 16 mesh U.S. sieve. The granules so produced are driedat 50 to 60 C and passed through a 16 mesh U.S. sieve. The sodiumcarboxymethyl starch, magnesium stearate, and talc, previously passedthrough a No. 30 mesh U.S. sieve, are then added to the granules which,after mixing, are compressed on a tablet machine to yield tablets eachweighing 120 mg.

FORMULATION EXAMPLE 4

Capsules, each containing 40 mg of medicament are made as follows:Quantity Ingredient (mg/capsule) Active Ingredient  40.0 mg Starch 109.0mg Magnesium stearate  1.0 mg Total 150.0 mg

The active ingredient, starch, and magnesium stearate are blended,passed through a No. 20 mesh U.S. sieve, and filled into hard gelatincapsules in 150 mg quantities.

FORMULATION EXAMPLE 5

Suspensions, each containing 50 mg of medicament per 5.0 mL dose aremade as follows: Ingredient Amount Active Ingredient 50.0 mg Xanthan gum 4.0 mg Sodium carboxymethyl cellulose (11%) 50.0 mg Microcrystallinecellulose (89%) Sucrose 1.75 g Sodium benzoate 10.0 mg Flavor and Colorq.v. Purified water to  5.0 mL

The active ingredient, sucrose and xanthan gum are blended, passedthrough a No. 10 mesh U.S. sieve, and then mixed with a previously madesolution of the microcrystalline cellulose and sodium carboxymethylcellulose in water. The sodium benzoate, flavor, and color are dilutedwith some of the water and added with stirring. Sufficient water is thenadded to produce the required volume.

FORMULATION EXAMPLE 6

Capsules are made as follows: Quantity Ingredient (mg/capsule) ActiveIngredient  15.0 mg Starch 407.0 mg Magnesium stearate  3.0 mg Total425.0 mg

The active ingredient, starch, and magnesium stearate are blended,passed through a No. 20 mesh U.S. sieve, and filled into hard gelatincapsules in 425.0 mg quantities.

FORMULATION EXAMPLE 7

An injectable preparation buffered to a pH of 7.4 is prepared having thefollowing composition: Ingredients Amount Active Ingredient  0.2 gSodium Phosphate Buffer Solution (0.8 M) 10.0 ml DMSO  1.0 ml WFI q.s.to 100 ml

FORMULATION EXAMPLE 8

An injectable formulation is prepared having the following composition:Amount Ingredients (w/v %) Motexafin gadolinium 0.23% Motexafin lutetium0.20% Mannitol (USP)  5.0% Acetic Acid (5%) adjust to pH 5.4 Sterile WFI(USP) q.s. to 100%

The formulation is filled into a glass vials, which are then purged withnitrogen to exclude oxygen from the head space and then sealed.

It may be desirable or necessary to introduce the pharmaceuticalcomposition to the brain, either directly or indirectly. Directtechniques usually involve placement of a drug delivery catheter intothe host's ventricular system to bypass the blood-brain barrier. Onesuch implantable delivery system used for the transport of biologicalfactors to specific anatomical regions of the body is described in U.S.Pat. No. 5,011,472 which is herein incorporated by reference.

Indirect techniques, which are generally preferred, usually involveformulating the compositions to provide for drug latentiation by theconversion of hydrophilic drugs into lipid-soluble drugs. Latentiationis generally achieved through blocking of the hydroxy, carbonyl,sulfate, and primary amine groups present on the drug to render the drugmore lipid soluble and amenable to transportation across the blood-brainbarrier. Alternatively, the delivery of hydrophilic drugs may beenhanced by intra-arterial infusion of hypertonic solutions which cantransiently open the blood-brain barrier.

Other suitable formulations for use in the present invention can befound in Remington's Pharmaceutical Sciences, Mace Publishing Company,Philadelphia, Pa., 17th ed. (1985).

Abbreviations

In the examples the following abbreviations have the following meanings.If an abbreviation is not defined, it has its generally acceptedmeaning. Cd-Tex = compound of formula A where M is Cd²⁺ Co-Tex =compound of formula A where M is Co²⁺ Dy-Tex = compound of formula Awhere M is Dy³⁺ Eu-Tex = compound of formula A where M is Eu³⁺ Gd-Tex =motexafin gadolinium (formula A where M is Gd³⁺) HPLC = high performanceliquid chromatography Lu-Tex = motexafin lutetium (formula A where M isLu³⁺) mg = milligram mL = milliliter mm = millimeter mM = millimolarMnTex = compound of formula II where M is Mn²⁺ mmol = millimoles nm =nanometer psi = pounds per square inch SmTex = compound of formula Awhere M is Sm³⁺ YTex = compound of formula A where M is Y³⁺ μL = microliter μM = micro molar HepG2 = a type of hepatocyte (liver) cancer cell

1-20. (canceled)
 21. A method for treating atherosclerotic inflammationin a mammal, said process comprising administering to the mammal: (a) areducing agent; and (b) a compound of Formula I

its hydrate, pharmaceutically acceptable salt or prodrug form thereof,wherein: M represents H or a metal cation; Q represents an integer offrom about −5 to about +5; L represents a charge balancing species; nrepresents an integer of from 0 to +5; Z¹, Z² and Z³ independentlyrepresent N, O, CH or S; R¹, R^(1a), R², R³, R⁴, R^(4a), R⁷, and R⁸ areindependently selected from acyl, acyloxy, optionally substitutedalkenyl, optionally substituted alkoxy, optionally substituted alkyl,optionally substituted alkynyl, optionally substituted amino, optionallysubstituted aryl, optionally substituted aryloxy, carboxyl, (optionallysubstituted alkoxy)carbonyl, (optionally substituted amino)carbonyl,(optionally substituted alkoxy)carbonyloxy, (optionally substitutedamino)carbonyloxy, cyano, optionally substituted cycloalkyl, optionallysubstituted cycloalkenyl, halogen, optionally substituted heteroaryl,optionally substituted heteroaryloxy, optionally substitutedheterocyclyl, optionally substituted heterocyclooxy, hydrogen, hydroxyl,nitro, optionally substituted azo, S—R³, SO—R³¹, SO₂—R³¹, and the moietyX—Y; R⁶ and R⁹ are independently selected from acyl, acyloxy, optionallysubstituted alkenyl, optionally substituted alkoxy, optionallysubstituted alkyl, optionally substituted alkynyl, optionallysubstituted amino, optionally substituted aryl, optionally substitutedaryloxy, carboxyl, (optionally substituted alkoxy)carbonyl, (optionallysubstituted amino)carbonyl, (optionally substituted alkoxy)carbonyloxy,(optionally substituted amino)carbonyloxy, cyano, optionally substitutedcycloalkyl, optionally substituted cycloalkenyl, fluoro, chloro, bromo,optionally substituted heteroaryl, optionally substituted heteroaryloxy,optionally substituted heterocyclyl, optionally substitutedheterocyclooxy, hydrogen, hydroxyl, nitro, optionally substituted azo,sulfanyl, sulfinyl, sulfonyl, and the moiety X—Y; R⁵, R¹⁰, R¹¹ and R¹²are independently selected from acyl, optionally substituted alkoxy,optionally substituted alkyl, optionally substituted aryl, halo,hydrogen, hydroxy, optionally substituted cycloalkyl, optionallysubstituted cycloalkenyl, optionally substituted heteroaryl, andoptionally substituted heterocyclyl; X is a covalent bond or a linker; Yis a catalytic group, a chemotherapeutic agent or a site-directinggroup; R³¹ represents acyl, optionally substituted alkenyl, optionallysubstituted alky, optionally substituted alkoxy, optionally substitutedalkoxycarbonyl, optionally substituted alkynyl, optionally substitutedaminocarbonyl, optionally substituted aryl, carboxy, optionallysubstituted cycloalkyl, optionally substituted heteroaryl, or optionallysubstituted heterocyclyl.
 22. A process of claim 21 wherein the compoundof Formula I is represented by

its hydrate, pharmaceutically acceptable salt or prodrug form thereof,wherein: M represents a metal cation selected from Gd(III) and Lu(III);Q represents an integer of 2; L represents a charge balancing speciesselected from OAc, NO₂, Cl, and PO₄; n represents an integer of 2; Z¹,Z² and Z³ independently represent N; R¹ and R^(1a) independentlyrepresent (CH₂)₃OH; R² and R³ independently represent C₂H₅; R⁴ andR^(4a) independently represent CH₃; R⁷ and R⁸ independently representO—(CH₂—CH₂—O)₃—CH₃; and R⁵, R⁶, R⁹, R¹⁰, R¹¹ and R¹² independentlyrepresent H.
 23. A process of claim 22 wherein the reducing agent andthe compound of Formula

wherein M independently at each occurrence represents Gd(III), Lu(III),Eu(III), Tb(III), Dy(III), Ho(III), Er(III), Tm(III), Yb(III), orY(III); and n represents an integer from 1 to 3; are intravenouslyadministered to the host.
 24. A process of claim 23 wherein the reducingagent is selected from ascorbic acid, dehydroascorbate, dihydrolipoate,NADH, folate, glyoxal, glyoxalate, oxamate, dimethyloxalate, oxamide,NADPH, glutathione, nacetylcystein and pyruvate.
 25. A process of claim24 wherein the reducing agent is administered at least about 30 minutesbefore administering a compound of Formula I.
 26. A process of claim 25wherein the reducing agent and a compound of Formula I are administeredsimultaneously to the host.